US Had Massive Atomic “Cannon” To Fire Nuclear Weapons

by Maya Carlin, Warrior Contributor, Weapons

In the first half of the twentieth century, the United States was the only nation to possess atomic weapons. By 1949, however, the American monopoly on atomic weaponry changed when the former USSR exploded an atomic bomb.

Igniting the arms race that would consume the Soviet Union and America for decades to come, atomic weaponry would soon become a staple in military arsenals in the Cold War-era. Perhaps the most unique weapon that emerged during this time period was a nuclear cannon dubbed “Atomic Annie.”

Officially designated the M65 280mm Motorized Heavy Gun, the cannon was only fired once.

Notably, the cannon could fire a nuclear round packed with as much explosive power as the bomb that devastated Hiroshima. While Atomic Annie was ultimately rendered obsolete due to the creation of other mobile rocket systems, the atomic cannon remains a favorite among military buffs.

A brief overview of Atomic Annie

After the USSR exploded an atomic bomb for the first time in the late 1940’s, U.S. engineers went to work to develop a nuclear-capable artillery piece. Then-president Dwight Eisenhower envisioned a peaceful strategic impetus for the development of an atomic cannon. In an effort to reduce defense budgets, the former president thought that nuclear weapons could reduce the cost and reliance on soldiers and conventional weapons alike.

As detailed by the National Park Service, Eisenhower “feared the effects of a broad Cold War fight on America’s economy and society. Increased military spending could warp the marketplace, while efforts to combat Communism at home, if not carefully regulated, might ultimately undermine American civil liberties.”

The original designs of the weapon were largely derived from the 240mm howitzer shell and German K5 railroad gun. The nickname Atomic Annie actually stems from a pair of German K5 guns that were used against U.S. landings in Italy. The resulting prototype resembled a large fire engine with two horsepower tractors positioned at each end.