What Would it Take for the U.S. Military to Use Force Again? Listen Download Embed Share Share this on Facebook (Opens in a new window) Share this on Twitter (Opens in a new window) Share this via Email A U.S. Marine watches as an Osprey carrying U.S. Secretary of Defense Leon Panetta arrives March 14, 2012 at Forward Operating Base Shukvani, Afghanistan. ( Scott Olson / Getty ) Produced by PRI and WNYC