NEWYou can now listen to Fox News articles! Hollywood Marine veteran Rob Riggle has doubts about whether today's stars would be willing to step away from the spotlight to serve in uniform like WWII bomber pilot Jimmy Stewart.Stewart famously walked away from an Oscar-winning career at its peak to enlist in the U.S. Army Air Corps as a private nine months before the attack on Pearl Harbor.In the upcoming biopic "Jimmy," Riggle, who is a retired U.S. Marine officer, plays Colonel Terrill, Stewart's squadron commander and mentor.TOM HANKS PUT 'BAND OF BROTHERS' STARS IN THEIR PLACE DURING BOOT CAMP 'MUTINY',...