After the bombing of Pearl Harbor drew the United States officially into World War II, the Navy determined it would need to build bases, roads, and airstrips in combat zones – and at warp speed. But who would build them?

Civilian contractors who built facilities at Wake Island were captured by Japanese soldiers 15 days after Pearl Harbor. They were taken as prisoners of war – in part – because as civilians, international law prohibited them from resisting attack from an enemy military. Those who tried were often executed.

On March 5, 1942, a true military construction force was established—the Naval Construction Regiment—with its construction battalions, known as CBs. Their motto is Construimus, Batuimus – “We Build, We Fight.”

These battalions, known as the Seabees, recruited persons with construction and engineering experience. While the enlistment age range was 18 to 50, several men older than 60 managed to get in, and the average age early in the war was 37.

More than 175,000 Seabees trained at the Naval Construction Battalion Center at Port Hueneme in Ventura County. By the time World War II ended, Seabees had been awarded 5 Navy Crosses, 33 Silver Stars, and over 2,000 Purple Hearts. They lost 272 enlisted men and 18 officers in battle, and more than 500 in construction accidents.

They became an integral part of the U.S. war machine, not only building facilities but often fighting the enemy to do so.

They assembled “Bailey Bridges” – trussed portable bridges still used today – over rivers, streams, and ravines, enabling equipment and personnel to advance. They carved roads throughout Southern Asia as part of the China-India-Burma Campaign. In one instance, they needed only 10 days to drive off the enemy on a Japanese-held island in the Pacific and construct headquarters for Admiral Chester Nimitz.

The Seabees played a major role in ending the war and saved hundreds of thousands of American lives in the process.

In July 1944, the Marines invaded Tinian Island in the North Marianas. Even as the fighting continued, the Seabees began building what, a year later, was the world’s largest airfield: four 8,500-foot-long runways to handle 1,000 B-29s.

On July 26, 1945, the USS Indianapolis delivered the innards of the “Little Boy” atomic bomb to Tinian. Eight days later, the Enola Gay dropped the first atomic bomb on Hiroshima. Three days after that, another B-29 – The Bockscar – dropped a second one on Nagasaki.

The death and destruction ultimately convinced the Japanese to surrender. Had President Truman decided against the bombs, the military would instead launch “Operation Downfall,” the code name for the invasion of Japan. The Allied command projected at least 1,000 American deaths per hour early in the invasion, 125,000 deaths overall, and as many as one million dead and wounded combined. Many more Japanese soldiers and citizens would die as well.

“It would have made D-Day seem like a piece of cake,” said Lonie Black of Turlock, a member of the 11^th Airborne Division who would have been part of the invading American force. “Knowing what it was going to be like, I cried like a baby, and I’m not ashamed to admit it.

“The way I look at it, I’ve been living on borrowed time for 64 years,” Black said in 2009, just four years before his death.

The Seabees, he said, helped him enjoy many more birthdays.

Today, and for the 80^th time, it’s their turn. Happy birthday, Seabees!