Bombing Iowa: Some ‘Balloon Bombs,“ launched by Japan, fell in Iowa

Iowa was bombed by Japan. How is it possible? Iowa is an inland state, 1,500 miles from the coast. How could a Japanese plane get that far and not be detected before reaching the Missouri or Mississippi River?

There was no plane, and no missile ever targeted the state. So, how did Japan manage to bomb such a distant place 8,000 miles away from its home islands in the Western Pacific? The answer is paper thin.

A Japanese plane dropped two bombs on Sept. 9, 1942 on Cape Blanco, Oregon, but that did not constitute a mass aerial assault.

But 81 years ago, on Nov. 3, 1944, an overseas enemy, for the first time since the War of 1812, launched a massive attack against the United States mainland.

The Japanese Army and Navy had been studying the jet stream at more than 35,000 feet in altitude with balloons and scientific instruments since the 1920s for an intended barrage of Russia after Japan conquered Manchuria in China.

The plan shifted focus in the late 1930s as the U.S. enacted economic sanctions against Japan for its invasion of China, and the Emperor’s High Command purchased weather maps from the U.S. Weather Bureau to analyze the jet stream patterns over the Pacific and into the North American continent.

Discovering that the prevailing winds would bring an object directly over the water to the western United States, three battalions of the Japanese Army formed a special division titled the Army Balloon Regiment. Composed of 2,800 warriors, their job was to develop and deploy a vehicle for delivering bombs all the way across the Pacific Ocean to the heartland of America.

Having experience with balloons. and now knowing the exact wind direction over the ocean and into the homeland of the enemy, balloons, under the direction of Lt. Commander, Koyashi Tanaka, were glued together forming five layers of paper and painted with a “rubber” dope, or varnish, that would seal it when the glue dried.

The paper formed a circle that when hydrogen was pumped in through a narrow nozzle at the bottom, caused the paper to fill with the gas until it created a perfect sphere, or shape of a ball.

That sphere, known as an envelope, grew to thirty-five feet in diameter, and a series of nineteen ropes, or shrouds as they were known, was attached around the circumference of the balloon so they could be pulled together and affixed to a thirty-two inch diameter ring that was suspended beneath it.

That ring was punctuated by seventy-two holes where black powder was inserted. Attached to these, and hanging below, was either a sandbag or four incendiary bombs, and, at the center of the ring, a high explosive bomb.

Aneroid barometers were attached to determine the balloon’s altitude, and based on that altitude, signal the ignition of the appropriate blow plugs so that its corresponding sandbag would drop off, lightening the load and assuring the balloon didn’t crash.

A battery was attached atop the barometer box to provide the spark, and a demolition charge about the size of a modern day cell phone. After the bombs were released, a flame would follow up another rope igniting the hydrogen and destroying the balloon.

Three bases were built to launch the balloons, which had come to be called Fugo, or “Windship Weapon,” north and east of Tokyo, including one at Fukushima.

Manned by nearly 3,000 personnel, those sites, with multiple launch pads at each, was able to send up a floating bomb balloon every half hour. The first, more for scientific purposes, was released on November 3, 1944. On Nov. 4, the U.S. Navy found the inaugural balloon 66 miles from San Pedro, California. Others, carrying ordnance, began arriving in Oregon, Montana, Wyoming, and the territory of Alaska, shortly thereafter.

On February 2, three months later, a mysterious object was found on the ground outside of Laurens, near Storm Lake. When investigators arrived, they perused a nearly fully intact balloon as well as its ballast ring, barometer, and all nineteen shrouds.

It had apparently malfunctioned, and after harmlessly dropping its bombs, fell to the earth without self destructing. The parts were picked up and brought to the Navy for storage and examination.

Twenty-six days later, near Holstein, in Ida County, another similar mysterious object was reported outside of town, this time containing scientific equipment to measure pressure and windspeed. No bombs had been attached to this, which was one of the early barometric study balloons. It, too, had landed causing no significant damage.

Two weeks after that incident, military investigators were once more called to Iowa when a flat sheet of bluish white colored paper lay flat surrounded by its shrouds, at Pocahontas, less than fifteen miles from the last sighting six weeks before, again hurting no one. In a month and a half, though, within a 60-mile radius, Northwest Iowa had been bombed three times by Japan.

Between November 1944 and April 1945, 6,000 balloon bombs had been launched. Of that enfilade, fortunately, only five Americans died in the attacks. Nonetheless, 81 years ago, in the winter of 1944-1945, the United States was invaded by an overseas nation for the first time in 132 years, and for the first time ever in Iowa.

Iowans quickly learned that it didn’t require a nuclear weapon, or machine gun, or even a pistol, to be the victim of a terror attack. It could come from a technology invented in the 18th century and from a place that was an ocean away. The nation learned even the American heartland was no longer a place of isolation.

David V. Wendell is a Marion historian, author and special events coordinator specializing in American history.