By Thomas McKinless

Following President Barack Obama’s announcement that 5,500 U.S. troops would stay in Afghanistan after 2016, Secretary of Defense Ashton B. Carter told reporters Thursday that while the situation in Afghanistan has improved, U.S. troops must remain in the region to maintain U.S. national security. “What I have learned over the last eight months is that Afghanistan is on a better path,” Carter said. “But more work lies ahead. And America’s national security remains very much at stake in that part of the world.”