by MATTHEW GAULT

At the end of World War II, America possessed the most powerful weapon in the world, but its method of using that weapon was primitive—it simply armed the bomb and tossed it out of a plane.

The Pentagon wanted better ways to deliver nuclear payloads, so it poured money into better bombs, missiles and even artillery.

In 1949, engineer and former Navy radar operator Robert Schwartz locked himself in a room inside the Pentagon and worked on the design for atomic artillery. The military only let him go home on Mondays. Fifteen days later, Schwartz emerged from the locked room with a design for a 280-millimeter gun—the massive M65 artillery cannon, known today as Atomic Annie.

The design impressed the Pentagon, and the military began production on the gun. She was 84 feet long, weighed 83 tons and took seven soldiers to operate her. She was ready by 1953, and Pres. Dwight D. Eisenhower showed the lumbering cannon off during his inaugural parade.

It was an opulent affair consisting of $100,000 in floats, three elephants, 350 horses, an Alaskan dog team and an M65 cannon. Everyone in the world now knew America had a brand new gun for its brand new weapon.

But Atomic Annie isn’t just the name for M65 cannons generally—it was once the specific name of one of the guns. The weapons were so huge and impressive that their crews gave them all nicknames. Battalions operating two of the guns in Europe nicknamed theirs Aphrodite and Cheyenne.

So which gun was the Atomic Annie? She was one of the first M65s ever made. But in 1953, she was just Able Annie—the Pentagon had yet to see what she could do.

The military brought Annie from her home at Fort Sill, Oklahoma to a testing range in Nevada. It needed to test her nuclear capabilities. They brought her brother—Sad Sack—along in case Annie failed.

She didn’t. At 8:30 in the morning on May 25, 1953, Annie fired an MK-9 atomic shell. It flew seven miles before exploding at a height of 524 feet above the ground. It was the first and last time she fired an atomic shell. The military filmed the test.

Her duty finished and her abilities proved, Able Annie was no longer just able—she was atomic. The military then planned to deploy Sad Sack to Europe, and send Atomic Annie back to Fort Sill to act as a prestige weapon.

But something went wrong.

The military mixed up the guns on the long drive home. Sad Sack went to Fort Sill and Annie went into the field.

Soldiers finally noticed the mix up while they cleaned Fort Sill’s cannon in preparation for the tenth anniversary of Annie’s test firing. The troops noticed the serial number was wrong. The gun wasn’t the lauded Annie … it was Sad Sack.

Atomic Annie was AWOL. And tracking her down was difficult. The Pentagon had produced 20 of the M65s and deployed them throughout Europe and the Pacific.

Their locations were top secret. Placing the artillery in classified locations throughout the world was one of America’s earliest attempts at nuclear deterrence. It would be another year before the military brought Annie in from the cold.