Approximately two months after the Japanese bombed Pearl Harbor, President Roosevelt signed Executive Order 9066, which authorized the war department to relocate thousands of Japanese and force them to live in internment camps — reportedly one-half were already U.S. citizens.
In Hawaii (which wouldn't become an American state until 1959), more than one-third of the island's population were first and second generation Japanese. They faced similar scrutiny as those living in the continental United States.
High ranking military advisors expressed concern with the Japanese currently serving in the armed forces because they believed their allegiance was with the enemy. This ideology caused many Japanese men and women to be relieved of their military duties.
Back in the States, many second-generation Japanese men, known as Nesei, detained in the internment camps wanted to show their devotion to the U.S. and decided to volunteer for military service.
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Impressed with the Japanese volunteers, the war department created an all-Nisei combat unit — the 100th infantry battalion. After a year of intense infantry training, they first deployed to North Africa and then took part in attacks on enemy forces in Monte Cassino, Italy.
In 1943, the 100th was reorganized and became part of the 442nd Regimental Combat Team, which included Nisei volunteers from Hawaii. The next year, they moved to the battlefields of France where they fought in eight major campaigns, and played a pivotal role the rescue the Texas 36th infantry division known as the "Lost Battalion."
The following year, the proud unit helped liberate the Jews from the first established Nazi concentration camp in Dachau, Germany.
In the Pacific, several Nisei troops worked as Japanese translators and were frequently mistaken for enemy combatants.
Sadly, in the two years of their combat effectiveness, 700 members of the original 13,000 were killed or labeled as missing in action.
After their war had ended, the proud men returned home and were celebrated by President Harry Truman for their devoted service.
"You fought not only the enemy but you fought prejudice, and you won," Truman addressed to the Nisei during a ceremony. "Keep up that fight, and we will continue to win."
Altogether, the men received 9,486 Purple Hearts, 4,000 Bronze Stars, and 21 Medals of Honor.