The apparently aggressive moniker U.S. Marines of the 1st 8-inch Howitzer Battery gave to their M55 self-propelled cannon probably has a much deeper meaning. Before America became fully involved in Vietnam, 19-year old songwriter P.F. Sloan wrote “Eve of Destruction.” The piece was influenced by the aftermath of the Kennedy assassination, the threat of nuclear war, racial tensions in America, and conflict overseas.

Performed by Dylanesque folk artist Barry McGuire in 1965, “Eve of Destruction” was hastily recorded late one evening that summer in just one take. It was a B-side originally, and true to the oldest of pop music legends, the story goes that a radio DJ at KFWB in Los Angeles mistakenly played it instead of “What’s Exactly the Matter with Me” on the other side.

Though frowned upon by many in the establishment in America and banned by some radio stations, the song became a popular anti-war anthem as the fighting in Vietnam escalated. Despite the controversy, “Eve” defiantly climbed to #1 in the U.S. and #3 in the UK.

Which brings us to the Marines, rolling into South Vietnam that same year. One lyric in particular, “You’re old enough to kill but not for votin’,” may have captured their imagination of the young men going into combat. And while the words on the side of the big 203mm gun seem hostile, it is most likely a sly bit of protest for a war that would go on throughout the 1960s and well into the 1970s.

Cory Graff is the military aviation curator at the Flying Heritage Collection.