8,500 U.S. troops are on heightened alert for deployment to Europe after Russia stationed more than 100,000 military personnel on its border with Ukraine. Europe's considerable economic links to Russia have complicated the response to the Kremlin's threats against Ukraine.This episode: White House correspondent Tamara Keith, White House correspondent Scott Detrow, and international affairs correspondent Jackie Northam.Connect:Email the show at nprpolitics@npr.orgJoin the NPR Politics Podcast Facebook Group.Subscribe to the NPR Politics Newsletter.Find and support your local public radio station.