Military officials who had become frustrated with dealing with Mr. Trump, an unpredictable president who often blindsided them with tweets stating that American troops would be coming home from one military engagement or another, said the chance to deal with a president who would actually follow a policy process before announcing a decision was a welcome one. But they also knew from the start that the methods they had employed with Mr. Trump were likely to no longer work.
The Defense Department had fended off an effort by Mr. Trump to abruptly pull out all remaining U.S. troops by last Christmas. Mr. Trump eventually ordered the force cut roughly in half — to 2,500, the smallest presence in Afghanistan envisioned by American counterterrorism planners, from 4,500.
In the new president, Pentagon officials and top commanders were holding on to the hope that because Mr. Biden had campaigned during the Obama years to keep a small counterterrorism force in Afghanistan (as opposed to 100,000 troops), they might have a more sympathetic ear.
Shortly after Mr. Austin was sworn in on Jan. 22, two days after the inauguration, he, General Milley and two top military officers — Gen. Austin S. Miller, the commander of U.S. forces in Afghanistan, and Gen. Kenneth F. McKenzie Jr., the head of the military’s Central Command, were in lock step in recommending that about 3,000 to 4,500 troops stay in Afghanistan.
The Pentagon’s behind-the-scenes effort got a lift from a congressionally appointed panel led by a friend of all four men: Gen. Joseph F. Dunford Jr., a retired four-star Marine general who was also a former top commander in Afghanistan and past chairman of the Joint Chiefs of Staff. On Feb. 3, it recommended that the Biden administration should abandon the May 1 exit deadline negotiated with the Taliban and instead reduce American forces further only as security conditions improved.
The report by the Afghanistan Study Group, a bipartisan panel examining the peace deal reached in February 2020 under the Trump administration, found that withdrawing troops based on a strict timeline, rather than how well the Taliban adhered to the agreement to reduce violence and improve security, risked the stability of the country and a potential civil war once international forces left.