slang A somewhat derogatory term United States Marine, possibly alluding to a sandbag's ability to catch and stop bullets. Popularized during the Gulf War from 1990–1991. Primarily heard in US. I heard Congress is sending even more self-propelled sandbags to Kuwait.
self-propelled sandbag
n. a U.S. Marine. (Persian Gulf War.) Those guys are just self-propelled sandbags. They are fearless.