“Remember Pearl Harbor!” “Loose Lips Might Sink Ships.” Those are among the most famous slogans of World War II. But another poster child birthed during the war—Smokey Bear—might be even better remembered. The ad campaign that spawned the cartoonish bear, and a fire prevention legend, was only made possible by wartime paranoia about the possibility of a Japanese invasion of the continental United States.

At the time, many Americans worried that explosive devices might spark forest fires along the Pacific coast—for which the U.S. was hardly prepared.

World War II was a tricky time for forest fire fighting. In the face of wartime rationing, it became harder and harder to get ahold of modern firefighting equipment. As more and more male firefighters joined the war efforts, officials faced a dilemma. “Foresters feared that the forest fire problem might soon get out of hand unless the American public could be awakened to [its] danger,” explained forestry researcher J. Morgan Smith.

It took an attack on U.S. soil to drive the danger home. In February 1942, a Japanese submarine shelled the Ellwood Oil Field a few miles north of Santa Barbara, California. The 20-minute-long shelling missed its mark; there were no injuries and it inflicted little damage. But it was one of the few attacks of the war that took place on U.S. soil.

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The shelling sparked a national invasion panic, with speculation as to just what Axis fighters could be capable of on U.S. soil. The specter of devastating fires loomed large. Not only were local men assisting with the war effort instead of watching for fires, but firefighting had long been considered a local concern.

Though federal funds had been going toward forest fire fighting since the early 20th century, there was no national effort to fight forest fires. The Ellwood shelling was enough to spark a cooperative effort. State forestry services and the Forest Service joined the newly created War Advertising Council to create the Cooperative Forest Fire Prevention Program in 1942.

The program focused on public service advertising, and posters urging the public to aid the war effort by preventing forest fires were soon splashed across the country. In 1944, the program enlisted a famous poster child, Disney’s Bambi. But Disney only lent the character to the effort for a year.

Artist Albert Staehle, known for his illustrations of adorable animals, stepped into the gap. He created the first poster of a cartoonish bear pouring water on a campfire. The Forest Service named the character after a former firefighting legend, New York assistant fire chief Smokey Joe Martin. In 1950, a real-life bear cub saved during a forest fire in New Mexico was adopted by the Forest Service, given Smokey’s name, and brought to the National Zoo. During his 26-year tenure at the zoo, Smokey Bear became a national icon—and the words “Only YOU Can Prevent Forest Fires” a nationally known catchphrase.

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Ironically, the only real enemy attempts to burn U.S. forests were failures. More than 9,000 Japanese fire balloons were launched over the western United States between 1944 and 1945, but the weapons caused few casualties and even less fire damage.

Over the next 75 years, Smokey's message of forest fire prevention successfully raised awareness of the dangers of unattended fires—but is also thought to have turned public opinion against burns of any kind. Ironically, the bear helped put the brakes on controlled burns, which keep the amount of flammable brush under control and help encourage new growth in forests.

While Smokey’s message has since been updated to mention “wildfires” instead of “forest fires” and to support prescribed fires while still preventing “unwanted and unplanned outdoor fires,” the “Smokey Bear effect” has been blamed for making U.S. forests less resilient in the face of climate change.

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