SEOUL — North Korea launched two ballistic missiles off its east coast on Wednesday, the country’s first ballistic missile test in six months and a violation of multiple United Nations Security Council resolutions that ban North Korea from conducting such tests.
Hours after the missiles were launched, South Korea announced that its president, Moon Jae-in, had just attended the test of the country’s first submarine-launched ballistic missile, making South Korea the seventh country in the world to operate S.L.B.M.s, after the United States, Russia, China, Britain, France and India.
The missile tests by both Koreas on the same day dramatically highlighted the intensifying arms race on the Korean Peninsula as nuclear disarmament talks between Washington and North Korea remained stalled. They also underscored the growing concern over regional stability, with Prime Minister Yoshihide Suga of Japan calling the North Korean missile launch “outrageous” and a threat to peace.
In its announcement, South Korea revealed that it had successfully developed a supersonic cruise missile and a long-range air-to-land missile to be mounted on the KF-21, a South Korean supersonic fighter jet, and that it had developed a ballistic missile powerful enough to penetrate North Korea’s underground wartime bunkers.
test-fired what it called newly developed long-range cruise missiles over the weekend. But the United States has not imposed fresh sanctions against the North for weapons tests in recent years. When North Korea resumed testing short-range ballistic missiles in 2019, Donald J. Trump, then the president, dismissed them for being short range.
The Biden administration has said it would explore “practical” and “calibrated” diplomacy to achieve the goal of the complete denuclearization of the Korean Peninsula. But North Korea has yet to respond to the administration’s invitation to dialogue.
“Rather than strengthen sanctions and military exercises, the allies have emphasized a willingness for dialogue and humanitarian cooperation,” said Leif-Eric Easley, a professor of international studies at Ewha Womans University in Seoul. “The problem with less than robust responses to North Korea’s tests is that deterrence can be eroded while Pyongyang advances its capabilities and normalizes its provocations.”
The North Korean missiles on Wednesday — launched from Yangdok, in the central part of the country — flew 497 miles and reached an altitude of 37 miles before landing in the sea between North Korea and Japan, the South Korean military said. South Korean and United States defense officials were analyzing the data collected from the test to determine exactly what type of ballistic missiles were used, it said.
Japan’s Ministry of Defense issued a statement saying that it “assumed” the missile did not reach the country’s territorial waters or its exclusive economic zone.
The news of the North Korean missile test broke shortly after Foreign Minister Wang Yi of China, North Korea’s biggest supporter and only remaining major trading partner, finished a meeting with his South Korean counterpart, Chung Eui-yong, in Seoul.
“It’s not just North Korea, but other countries as well that engage in military activities,” Mr. Wang said when asked by reporters to comment on the North’s weekend cruise-missile test. “We must all work together to resume dialogue. We all hope to contribute to peace and stability on the Korean Peninsula.”
Mr. Wang didn’t elaborate, but appeared to be referring to the joint military exercises conducted by the United States and South Korea last month. North Korea has accused Washington and Seoul of preparing to invade the North, and usually counters joint military drills between the two allies with its own military exercise or weapons tests.
“The United States has no hostile intent toward” North Korea, Sung Kim, the Biden administration’s special envoy, said on Tuesday in Tokyo, where he met with representatives from Japan and South Korea to discuss the North’s arsenal. He said Washington hoped that North Korea would “respond positively to our multiple offers to meet without preconditions.”
The latest tests showed that North Korea continued to improve its arsenal of missiles despite a series of resolutions from the United Nations Security Council that banned North Korea from developing or testing ballistic missiles and nuclear weapons.
Tensions on the Korean Peninsula rose sharply in 2017, when North Korea tested three intercontinental ballistic missiles and conducted its sixth underground nuclear test, leading to the sanctions from the United Nations. After the tests, the country claimed an ability to target the continental United States with a nuclear warhead.
Mr. Trump met with Kim Jong-un, the North Korean leader, three times between 2018 and 2019, but the leaders failed to reach an agreement on lifting sanctions or rolling back the North’s nuclear and missile programs. Mr. Kim has since vowed to boost his country’s weapons capabilities.
With the recent tests, “North Korea is seeking to increase its leverage in coming talks” with Washington, said Lee Byong-chul, a North Korea expert at Kyungnam University’s Institute for Far Eastern Studies in Seoul.
By timing its latest test to Mr. Wang’s visit to Seoul, North Korea also appeared to “express discontent with Beijing” that it was not providing enough economic assistance during the global health crisis, Mr. Lee said.
North Korea’s economy, already battered by years of devastating international sanctions, has suffered greatly as trade with China has plummeted in the coronavirus pandemic.
SEOUL — North Korea said on Monday it had successfully launched newly developed long-range cruise missiles, its first missile test in six months and a new indication that an arms race between North and South Korea was heating up on the Korean Peninsula.
In the tests that took place on Saturday and Sunday, the North Korean missiles hit targets 1,500 kilometers (932 miles) away after flying more than two hours, said the North’s official Korean Central News Agency. The missiles changed their trajectories and made circles before hitting their targets, it said.
A series of resolutions from the United Nations Security Council banned North Korea from developing or testing ballistic missiles, but not cruise missiles. A cruise missile test by the North usually does not raise as much alarm as its ballistic missile tests. The country’s state-run media also indicated that the nation’s leader, Kim Jong-un, had not attended the weekend tests, though he has usually supervised all major weapons tests in recent years.
The latest tests showed that North Korea continued to improve its arsenal of missiles while nuclear disarmament talks with the United States remained stalled. North Korea said on Monday that the long-range cruise missile was “a strategic weapon of great significance” and part of an arms development goal announced by Mr. Kim during the party congress in January.
ramping up its own arms buildup.
Dosan Ahn Changho-class attack submarine. North Korea began testing its submarine-launched ballistic missiles in 2015, reporting the “greatest success” the following year.
As international negotiations have made little progress in stopping North Korea from growing its weapons arsenal, South Korea has embarked on building more powerful missiles and missile-defense systems of its own to counter North Korean threats.
launched its first intercontinental ballistic missile in 2017, Donald J. Trump, then president, lifted the payload limit on South Korean ballistic missiles. During the summit meeting in May between President Biden and his South Korean counterpart, Moon Jae-in, the allies agreed to terminate the missile guidelines, leaving South Korea free to develop longer-range missiles.
North Korea reacted angrily to the removal of the missile restrictions, calling it “a stark reminder of the U.S. hostile policy.”
The removal of the limits allows South Korea to build ballistic missiles with larger warheads that hold destructive power and that can target underground bunkers where North Korea keeps its nuclear arsenal and where its leadership would hide at war, military analysts said.
When Mr. Moon visited his Defense Ministry’s Agency for Defense Development last year, he said South Korea had “developed a short-range ballistic missile with one of the largest warheads in the world,” an apparent reference to the Hyunmoo-4, which missile experts say can cover all of North Korea with a two-ton payload.
When North Korea last conducted a missile test, on March 25, it said it had launched a new ballistic missile that carried a 2.5-ton warhead. This month, reports emerged in South Korean news media that the South was developing an even more powerful weapon: a short-range ballistic missile with a payload of up to three tons.
The tit-for-tat weapons buildup signaled that the rival militaries were arming themselves with increasingly powerful missiles that can fly farther and carry more destructive power, and that are harder to intercept.
said this month.
last October and in January, North Korea unveiled what appeared to be newly developed intercontinental and submarine-launched ballistic missiles. The United Nations’ nuclear watchdog said last month that the country appeared to have restarted a reactor in its main nuclear complex.
But North Korea has refrained from testing an I.C.B.M. or a nuclear device since 2017. Its most recent military parade, held Thursday to mark the government’s 73rd anniversary, did not feature new weapons.
Mr. Dermer, now a private citizen but still a confidante of Mr. Netanyahu’s, said the Biden administration was “engaged in an accommodation of Iran at best, and appeasement of Iran at worst.”
“It’s disastrous for Israel’s national security,” he added.
During his joint appearance with Mr. Netanyahu, Mr. Blinken said the administration was “consulting closely with Israel, as we did today, on the ongoing negotiations in Vienna around a potential return to the Iran nuclear agreement, at the same time as we continue to work together to counter Iran’s destabilizing actions in the region.”
With a fifth national election in two years possible in Israel, the long-embattled Mr. Netanyahu’s days in power may be numbered. But David Makovsky, the director of the Koret Program on Arab-Israel Relations at the Washington Institute for Near East Policy, said he sees no immediate successor to Mr. Netanyahu who is more amenable to the nuclear deal.
Mr. Makovsky said Israeli officials hope to avoid the acrimony with Washington that characterized Mr. Obama’s nuclear talks with Iran. Mr. Netanyahu openly denounced the deal as lacking sufficient limits on Iran’s nuclear activity, in part because many restrictions phase out after a decade, and as failing to address Iran’s support of anti-Israel proxies like Hamas and Lebanon-based Hezbollah.
But he added that Israeli officials have grown skeptical of talk from Mr. Blinken and other Biden officials about a potential “longer and stronger” deal that would address Iran’s ballistic missile program and support for proxies.
The prospects for a revived nuclear deal not only hinge on negotiations in Vienna, but on electoral politics in Tehran, where a list of seven contenders for the presidential elections next month was announced Tuesday by a panel of clerics that vets the candidates.
Two associates of President Hassan Rouhani, a moderate who was an architect of the original nuclear deal, were disqualified from the final list on Tuesday, virtually guaranteeing that the next president will be a conservative hard-liner closely aligned with the supreme leader, Ayatollah Ali Khamenei. The candidate most favored to win is Ebrahim Raisi, the head of the judiciary.
WASHINGTON — Iran agreed on Monday to a one-month extension of an agreement with international inspectors that would allow them to continue monitoring the country’s nuclear program, avoiding a major setback in the continuing negotiations with Tehran.
Under the agreement with the International Atomic Energy Agency, Iran will extend access to monitoring cameras at its nuclear facilities until June 24, Rafael Mariano Grossi, the agency’s director general, told reporters in Vienna.
The extension prevents a new crisis that could derail talks among world powers, including the United States, aimed at bringing Washington back to the 2015 nuclear deal that President Donald J. Trump withdrew from three years ago. Restoring the deal, including a commitment from Iran to resume all its obligations under the agreement, is a top priority for President Biden.
Iran’s Supreme National Security Council said in a statement that the decision was made “so that negotiations have the necessary chance to progress and bear results.”
reached a three-month compromise under which inspectors would retain partial access to nuclear production facilities.
Under that agreement, Iran allowed cameras to continue monitoring its facilities but insisted on retaining possession of the footage until an agreement to restore the larger nuclear deal was reached. The country’s state media reported on Monday that it would share the footage with the International Atomic Energy Agency if the United States lifted sanctions as part of a restored deal, but would erase the recordings otherwise.
The agreement will allow for other methods of continued international visibility into the nuclear program, but neither Iran nor the agency has publicly provided full details about their compromise.
“I want to stress this is not ideal,” Mr. Grossi said. “This is like an emergency device that we came up with in order for us to continue having these monitoring activities.”
sanctions that are strangling Iran’s oil exports and economy.
Because Tehran refuses to negotiate directly with the United States over the 2015 deal, which it says that Mr. Trump violated without cause, American negotiators have been working from a nearby hotel and communicating with Iranian officials through intermediaries.
Appearing on “This Week” on ABC on Sunday, Secretary of State Antony J. Blinken said that the talks had made progress but suggested that Tehran was delaying further progress.
“Iran, I think, knows what it needs to do to come back into compliance on the nuclear side. And what we haven’t yet seen is whether Iran is ready and willing to make a decision to do what it has to do,” he said. “That’s the test, and we don’t yet have an answer.”
on Twitter. He asked if the United States was ready to return to the deal by lifting the sanctions and said that Iran would return to its full commitments once Washington had done so.
“Lifting Trump’s sanctions is a legal & moral obligation,” Iran’s foreign minister, Javad Zarif, tweeted on Sunday. “NOT negotiating leverage.”
He added of the sanctions, “Didn’t work for Trump — won’t work for you.”
Iran has steadily expanded its nuclear program since Mr. Trump’s withdrawal from the deal. Its government said on Monday that the stockpile of enriched uranium at higher levels had increased in the past four months.
Iran now has a stockpile of 2.5 kilograms of uranium enriched to 60 percent purity, 90 kilograms of enriched uranium at 20 percent and 5,000 kilograms of enriched uranium at 5 percent, Ali Akbar Salehi, the head of the country’s Atomic Energy Organization, told state television.
Uranium enriched to 60 percent purity is a relatively short step from bomb fuel, which is typically considered 90 percent or higher. While uranium enriched to 60 percent can be used as fuel in civilian nuclear reactors, such applications have been discouraged globally because it can easily be turned into bomb fuel.
The nuclear deal with world powers capped Iran’s enrichment and stockpiling of nuclear material at 2.2 kilograms of uranium enriched to a level of 3.7 percent.
This obituary is part of a series about people who have died in the coronavirus pandemic. Read about others here.
For nearly four decades, William R. Harris devoted his career to safeguarding his fellow citizens.
As an international lawyer and a sought-after consultant, he drafted treaties to prevent the proliferation of nuclear weapons and reduce the risk of accidental war. He modeled a framework for the government to continue functioning during a national catastrophe. He helped extend Daylight Saving Time to conserve fuel and focused officials on protecting the electrical grid from digital sabotage.
He practiced what he preached, too, making sure to get his first vaccination for the coronavirus in early February, as soon as he was eligible and the vaccine was available. He completed the regimen by the end of the month.
In late March, though, his family said, he received a jarring diagnosis: Covid-19. Mr. Harris also had chronic lymphocytic leukemia, and family members said that a few weeks after learning that he had Covid, he read an article in a scientific journal suggesting that the vaccine might not be fully effective for people with that type of leukemia.
The New York Times last month.
No vaccine is 100 percent effective, and some so-called breakthrough infections can be expected, even in healthy people who have been fully vaccinated. But those cases are rare. As of April 26, the Centers for Disease Control and Prevention reported 9,245 breakthrough cases, out of 95 million fully vaccinated Americans; 132 people died.
In a eulogy on Facebook, Mr. Harris’s daughter Darcy R. Harris described him this way: “As an international lawyer and policy wonk, his work spanned arms control treaties and verification, energy policy, space law. He was a consummate researcher, an early adopter, an innovator. On top of that, he was always working for free and helping others out.”
Dr. William A. Horwitz and Dr. Henriette Klein, both of whom were professors of clinical psychiatry at Columbia University.
He attended the Dalton School in Manhattan and, after graduating from the Choate School, now Choate Rosemary Hall, in Wallingford, Conn., earned a bachelor’s degree in history from Harvard College in 1962 and a law degree from Harvard Law School in 1966.
In 1968, he married Elizabeth Jones. Along with his wife and their daughter Darcy, he is survived by another daughter, Rebecca Harris Deane; a son, William Proctor Harris; four grandchildren; and his sister, Susan Harris Molnar.
President Biden and Iran’s leaders say they share a common goal: They both want to re-enter the nuclear deal that President Donald J. Trump scrapped three years ago, restoring the bargain that Iran would keep sharp limits on its production of nuclear fuel in return for a lifting of sanctions that have choked its economy.
But after five weeks of shadow boxing in Vienna hotel rooms — where the two sides pass notes through European intermediaries — it has become clear that the old deal, strictly defined, does not work for either of them anymore, at least in the long run.
The Iranians are demanding that they be allowed to keep the advanced nuclear-fuel production equipment they installed after Mr. Trump abandoned the pact, and integration with the world financial system beyond what they achieved under the 2015 agreement.
The Biden administration, for its part, says that restoring the old deal is just a steppingstone. It must be followed immediately by an agreement on limiting missiles and support of terrorism — and making it impossible for Iran to produce enough fuel for a bomb for decades. The Iranians say no way.
financial restrictions that go beyond that deal — mostly involving conducting transactions with Western banks — because it would create what one senior administration official called a “ripe circumstance for a negotiation on a follow-on agreement.”
The Iranians refuse to even discuss a larger agreement. And American officials say it is not yet clear that Iran really wants to restore the old deal, which is derided by powerful hard-liners at home.
campaign of sabotage and assassination to cripple the Iranian program — and perhaps the negotiations themselves. So it was notable that the director of the Mossad, who has led those operations, was recently ushered into the White House for a meeting with the president. After an explosion at the Natanz nuclear plant last month, Mr. Biden told aides that the timing — just as the United States was beginning to make progress on restoring the accord — was suspicious.
The split with Israel remains. In the meetings in Washington last week — which included Mr. Blinken; the C.I.A. director, William J. Burns; and the national security adviser, Jake Sullivan — Israeli officials argued that the United States was naïve to return to the old accord, which they think preserved a nascent nuclear breakout capability.
Mr. Biden’s top aides argued that three years of “maximum pressure” on Iran engineered by Mr. Trump and his secretary of state, Mike Pompeo, had failed to break its government or limit its support of terrorism. In fact, it had prompted nuclear breakout.
told the BBC.
Iran wants more sanctions lifted than the United States judges consistent with the deal, while insisting on keeping more of its nuclear infrastructure — in particular advanced centrifuges — than that deal permits. Instead, Iran argues that the International Atomic Energy Agency should simply inspect the new centrifuges, a position that is unacceptable to Washington.
While the talks continue, Iran is keeping up the pressure by adding to its stockpile of highly enriched uranium and the equipment to make it, all in violation of the deal.
Both Iran and the United States are working under delicate political constraints. Even as Iran’s supreme leader, Ayatollah Ali Khamenei, has supported the Vienna talks, Mr. Rouhani and Mr. Zarif are mocked by powerful conservatives who do not trust Washington and who expect to capture the presidency.
For his part, Mr. Biden must contend with a Congress that is highly skeptical of a deal and largely sympathetic to the concerns of Israel.
increasing enrichment to just short of bomb grade in small quantities and barring international inspectors from key sites in late February — Mr. Zarif insists that these moves are easily reversible.
American intelligence officials say that while Iran has bolstered its production of nuclear material — and is probably only months from being able to produce enough highly enriched uranium for one or two bombs — even now, there is no evidence Iran is advancing on its work to fashion a warhead. “We continue to assess that Iran is not currently undertaking the key nuclear weapons-development activities that we judge would be necessary to produce a nuclear device,” Avril D. Haines, the director of national intelligence, said in a report last month.
scandal over Mr. Zarif, whose criticism of internal decision-making recently leaked, apparently in an effort to damage his reputation and any chance he had to run for the presidency.
Ayatollah Khamenei refuted the criticism without naming Mr. Zarif, but he said the comments were “a big mistake that must not be made by an official of the Islamic Republic” and “a repetition of what Iran’s enemies say.”
At the same time, by downplaying Mr. Zarif’s role, the supreme leader reaffirmed his support for the talks while also sheltering them from criticism by hard-liners, said Ellie Geranmayeh of the European Council on Foreign Relations.
Steven Erlanger reported from Brussels, and David E. Sanger from Washington. Farnaz Fassihi contributed reporting from New York.
President Biden will meet with President Moon Jae-in of South Korea in Washington on May 21, the White House announced on Thursday.
“President Moon’s visit will highlight the ironclad alliance between the United States and the Republic of Korea, and the broad and deep ties between our governments, people, and economies,” Jen Psaki, the White House press secretary, said in a statement. “President Biden looks forward to working with President Moon to further strengthen our alliance and expand our close cooperation.”
In an interview with The New York Times published last week, Mr. Moon urged Mr. Biden to sit down with North Korea and kick-start negotiations, calling denuclearization a “matter of survival” for South Korea.
Mr. Biden’s predecessor, Donald J. Trump, left office without removing a single North Korean nuclear warhead. Kim Jong-un, the leader of North Korea, has resumed weapons tests.
Prime Minister Yoshihide Suga of Japan at the White House on April 16, marking the first in-person visit of a foreign leader during his presidency.
SEOUL — President Moon Jae-in of South Korea has a message for the United States: President Biden needs to engage now with North Korea.
In an interview with The New York Times, Mr. Moon pushed the American leader to kick-start negotiations with the government of Kim Jong-un, the leader of North Korea, after two years in which diplomatic progress stalled, even reversed. Denuclearization, the South Korean president said, was a “matter of survival” for his country.
He also urged the United States to cooperate with China on North Korea and other issues of global concern, including climate change. The deteriorating relations between the superpowers, he said, could undermine any negotiations over denuclearization.
“If tensions between the United States and China intensify, North Korea can take advantage of it and capitalize on it,” Mr. Moon said.
work to achieve denuclearization and peace on the Korean Peninsula has since unraveled.
President Donald J. Trump left office without removing a single North Korean nuclear warhead. Mr. Kim has resumed weapons tests.
“He beat around the bush and failed to pull it through,” Mr. Moon said of Mr. Trump’s efforts on North Korea. “The most important starting point for both governments is to have the will for dialogue and to sit down face to face at an early date.”
Now in his final year in office, Mr. Moon is determined to start all over again — and knows he faces a very different leader in Mr. Biden.
annual threat assessment released last week, the United States’ director of national intelligence said Mr. Kim “believes that over time he will gain international acceptance and respect as a nuclear power.”
But Mr. Moon’s team argues that the phased approach is the most realistic, even if it is imperfect. As his administration sees it, North Korea would never give up its arsenal in one quick deal, lest the regime lose its only bargaining chip with Washington.
The key, Mr. Moon said, is for the United States and North Korea to work out a “mutually trusted road map.”
American negotiators under Mr. Trump never made it to that point. Both sides could not even agree on a first step for the North and what reward Washington would provide in return.
real-estate and other scandals. This month, angry voters delivered crushing defeats to his Democratic Party in the mayoral elections in South Korea’s two largest cities.
That is a sharp turn of fortune from the start of his administration, when Mr. Moon parlayed a hair-raising geopolitical crisis into a signature policy initiative.
“When I took office back in 2017, we were really concerned about the possibility of war breaking out once again on the Korean Peninsula,” he said.
Four days into his tenure, North Korea launched its Hwasong-12 intermediate-range ballistic missile that it said could target Hawaii and Alaska. Then the North tested a hydrogen bomb and three intercontinental ballistic missiles. In response, Mr. Trump threatened “fire and fury,” as American Navy carrier groups steamed toward the peninsula.
there is no longer a Nuclear Threat from North Korea.” When Mr. Kim and Mr. Trump met again in 2019 in Hanoi, Vietnam, the negotiations went nowhere, and the men left without an agreement on how to move forward with the Singapore deal.
While Mr. Moon was careful to dole out praise for Mr. Trump, he also seemed frustrated by the former president’s erratic behavior and Twitter diplomacy. Mr. Trump canceled or downsized the annual joint military drills that the United States conducts with the South and demanded what Mr. Moon called an “excessive amount” to keep 28,500 American troops in South Korea.
strike a deal within 46 days of Mr. Biden’s inauguration was a “clear testament to the importance President Biden attaches to” the alliance.
Mr. Moon is hopeful about the progress the new American leader can make on North Korea, although any significant breakthrough may be unrealistic, given the deep mistrust between Washington and Pyongyang.
Mr. Biden said last month that he was “prepared for some form of diplomacy” with North Korea, but that “it has to be conditioned upon the end result of denuclearization.”
North Korea has offered ideas on a phased approach starting with the demolition of its only-known nuclear test site, followed by the dismantling of a rocket engine test facility and the nuclear complex in Yongbyon north of Pyongyang.
Mr. Moon said he believed such steps, if matched with American concessions, could lead to the removal of the North’s more prized assets, like I.C.B.M.s. In that scenario, he said, the move toward complete denuclearization becomes “irreversible.”
“This dialogue and diplomacy can lead to denuclearization,” he said. “If both sides learn from the failure in Hanoi and put their heads together for more realistic ideas, I am confident that they can find a solution.”
SEOUL — Pride and jealousy have driven North and South Korea to engage in propaganda shouting matches and compete over who could build a taller flagpole on their border. Now that one-upmanship is intensifying a much more dangerous side of their rivalry: the arms race.
Earlier this month, South Korea’s dream of building its own supersonic fighter jet was realized when it unveiled the KF-21, developed at a cost of $7.8 billion. The country also recently revealed plans to acquire dozens of new American combat helicopters. When President Moon Jae-in visited the Defense Ministry’s Agency for Defense Development last year, he said South Korea had “developed a short-range ballistic missile with one of the largest warheads in the world.”
Unlike North Korea, the South lacks nuclear weapons. But in recent years the country has revved up its military spending, procuring American stealth jets and building increasingly powerful conventional missiles capable of targeting North Korean missile facilities and war bunkers.
Korea Institute for National Unification, a government-funded research group.
The two Koreas have long been locked in a perpetual arms race. But Pyongyang’s growing nuclear capabilities, coupled with the fear of a withdrawal of American troops from South Korea under President Donald J. Trump, added to those tensions.
While in office, Mr. Moon has increased South Korea’s annual military spending by an average of 7 percent, compared with the 4.1 percent average of his predecessor. After diplomacy failed to eliminate the North’s nuclear arsenal, Mr. Moon had to reassure South Koreans that their country was not a “sitting duck,” said Yoon Suk-joon, a researcher at the Korea Institute for Military Affairs.
Soon after Mr. Moon’s visit to the Agency for Defense Development, South Korean media reported that the weapon he referred to was the Hyunmoo-4, a missile tested last year. According to missile experts, the Hyunmoo-4 can fly 497 miles, enough to target all of North Korea. Its two-ton payload — unusually large for a short-range missile — could destroy the North’s underground missile bases.
launched a new ballistic missile of its own and said the weapon flew 372 miles with a 2.5-ton warhead. The test prompted Mr. Moon to claim the following day that South Korea had “world-class missile capabilities, enough to defend ourselves while abiding by our commitment to make the Korean Peninsula free of nuclear weapons.”
attacked a South Korean island with a rocket barrage in 2010, South Korea demanded that Washington ease the restrictions so it could build more powerful missiles.
“We hinted that we might scrap the missile guidelines unilaterally,” said Chun Yung-woo, the national security adviser at the time. “We told the Americans that if we didn’t address concern over the North’s growing nuclear and missile threat, more and more South Koreans would call for building nuclear bombs for ourselves.”
In 2012, Washington agreed to let South Korea deploy ballistic missiles with a range of up to 497 miles as long as it abided by the 1,100-pound warhead limit. It also said South Korea could exceed the payload limit by several times on missiles with shorter ranges.
South Korea has since tested missiles with growing ranges and bigger warheads, including the Hyunmoo-2A, Hyunmoo-2B and Hyunmoo-2C. Once North Korea launched its first intercontinental ballistic missile in 2017, Mr. Trump lifted the payload limit entirely, making way for the Hyunmoo-4.
short-range nuclear missiles aimed at South Korea and vowed to improve them by making the warheads “smaller, lighter and tactical.” South Korea’s strategy of deterrence has been based on the belief that the best chance it has against the North without nuclear weapons of its own is to build up a conventional missile defense and deploy ever more powerful “bunker busters” to make Mr. Kim fear for his life.
When North Korea tested its intercontinental ballistic missile in 2017, the United States and South Korea responded by launching their own ballistic missiles to demonstrate their “deep-strike precision” capabilities. In his book “Rage,” the journalist Bob Woodward wrote that the American missile traveled the exact distance between its launching point and the location from which Mr. Kim watched his I.C.B.M. launch.
collapsed, North Korea resumed tests in 2019, rolling out three short-range ballistic missiles that were designed to counter the allies’ antimissile capabilities.
North Korea’s old fleet of Scud and Rodong missiles used liquid fuel and lacked precision. The country’s new generation of missiles uses solid propellants, making them quicker to launch, easier to transport and more difficult to target. They also have greater accuracy and evasive maneuvering power that could confound the South’s missile defense systems.
The new solid-fuel ballistic missile North Korea tested in March likely evaded the allies’ radar during its low-altitude maneuvering, leading the South Korean military to estimate its range at 280 miles, not the 372 miles the North claimed, said Chang Young-keun, a missile expert at Korea Aerospace University. Mr. Chang said the missile could also likely increase range and warhead weight because it was powered by “the largest solid-fuel rocket motor developed and tested in North Korea so far.”
The North’s ICBMs still use liquid fuel, which takes hours to load before launching, making them vulnerable to American pre-emptive strikes. But in his January speech, Mr. Kim vowed to build solid-fuel ICBMs, presenting an even bigger challenge for American missile defenses. Such prospects deepen the fear among some South Koreans that Washington would be less likely to intervene if it, too, faced a possible North Korean nuclear attack.
Iran has started enriching its uranium supply to 60 percent purity — the closest the country has ever come to the level needed for a weapon — in response to the sabotage of an Iranian nuclear site last weekend linked to Israel.
The move by Iran, reported Friday on state media, made good on threats Iranian officials had announced after the sabotage, which have cast a new cloud over talks to save the 2015 deal limiting Iran’s nuclear abilities in exchange for sanctions relief.
President Hassan Rouhani of Iran has gone further, boasting as those talks resumed in Vienna that his scientists could easily enrich uranium to 90 percent purity — weapons-grade fuel — although he insisted, as Iranian leaders have repeatedly, that Iran “is never seeking to make an atomic bomb.”
So what is the significance of uranium’s purity, which is at the heart of the accord that negotiators are trying to rescue? And why is Iran making these claims? Some basic questions and answers:
What is the goal of uranium enrichment?
Uranium contains a rare radioactive isotope, called U-235, that can be used to power nuclear reactors at low enrichment levels and to fuel nuclear bombs at much higher levels. The goal of uranium enrichment is to raise the percentage levels of U-235, which is often done through the use of centrifuges — machines that spin a form of unrefined uranium at high speeds.
becomes far easier and requires fewer centrifuges as it moves into the higher purities. In other words, getting to 90 percent purity is much easier starting from 20 percent, and easier still starting from 60 percent.
How much enriched uranium does Iran now possess?
According to the International Atomic Energy Agency, the nuclear-monitoring arm of the United Nations, Iran as of February had amassed 2,967.8 kilograms of uranium — roughly 14 times the limit under the nuclear accord and theoretically enough to power about three atomic bombs if refined to weapons grade. The stockpile includes 17.6 kilograms enriched to 20 percent — also forbidden under the accord until the year 2030.
Did the sabotage last weekend set back Iran’s ability to enrich uranium?
Almost certainly yes. While Iranian officials have given conflicting accounts of the extent of centrifuge damage at Natanz, the sabotaged enrichment complex, at least one has said that several thousand of the machines were destroyed.But Iran also possesses a second known enrichment site, an underground facility called Fordow, that houses roughly 1,000 centrifuges, and some were deployed early this year to enrich uranium to 20 percent.
Mehrzad Boroujerdi, an Iran expert who is a professor and director of the School of Public and International Affairs at Virginia Tech. “It is getting punched left and right, without the ability to do damage to the other side.”
With the 60 percent enrichment, Mr. Boroujerdi said, Iran’s leaders “are trying to resort to any aces they may have.”