While powered armor is Starship Troopers' most famous legacy, its influence extends deep into contemporary militaries. Over half a century after its publication, Starship Troopers is on the reading lists of the United States Marine Corps and the United States Navy. It is the first science fiction novel on the reading lists at three of the five United States military branches. When Heinlein wrote Starship Troopers the United States military was a largely conscripted force, with conscripts serving two-year hitches. Today the U.S. military has incorporated many ideas similar to Heinlein's concept of an all-volunteer, high-tech strike force. In addition, references to the book keep appearing in military culture. In 2002 a marine general described the future of Marine Corps clothing and equipment as needing to emulate the Mobile Infantry. In 2012, an article on the US military buying ballistic face masks specifically referenced the "big steel gorilla[s]" of Starship Troopers.