Top U.S. military commanders, who only a few months ago were planning to pull the last American troops out of Afghanistan by year's end, are now quietly talking about an American commitment that could keep thousands of troops in the country for decades. The new American outlook marks a striking change for Obama, who campaigned on a promise to bring American troops home and has said repeatedly that he does not support the idea of endless war." And it highlights a major shift for the American military, which has spent much of the past decade racing to hit milestones as part of its broader "exit strategy" from Afghanistan and Iraq. These days, that phrase has largely disappeared from the military's lexicon. In its place, there is a broad recognition in the Pentagon that building an effective Afghan army and police force will take a generation's commitment, including billions of dollars a year in outside funding and constant support from thousands of foreign advisers on the ground. There are now 9,800 U.S. troops in Afghanistan. Plans call for Obama to halve that force by the time he leaves office, but he could defer the decision to the next president.