Louis was born in Brooklyn, New York, on the 19th of June, 1945, and after graduating from Archbishop Molloy High School in Queens, he attended SUNY Maritime College at Fort Schuyler. He withdrew from college and went to work as a lineman for a telephone company before being drafted for the US Army in 1966. He was deployed to the Republic of Vietnam with Company C, 1st Battalion, 12th Infantry Regiment, 4th Infantry Division and it was his actions on the 15th of February, 1967, that would earn him the Medal of Honor. The citation reads:

For conspicuous gallantry and intrepidity at the risk of his life above and beyond the call of duty. Pfc. Willett distinguished himself while serving as a rifleman in Company C, during combat operations. His squad was conducting a security sweep when it made contact with a large enemy force. The squad was immediately engaged with a heavy volume of automatic weapons fire and pinned to the ground. Despite the deadly fusillade, Pfc. Willett rose to his feet firing rapid bursts from his weapon and moved to a position from which he placed highly effective fire on the enemy. His action allowed the remainder of his squad to begin to withdraw from the superior enemy force toward the company perimeter. Pfc. Willett covered the squad's withdrawal, but his position drew heavy enemy machinegun fire, and he received multiple wounds enabling the enemy again to pin down the remainder of the squad. Pfc. Willett struggled to an upright position, and, disregarding his painful wounds, he again engaged the enemy with his rifle to allow his squad to continue its movement and to evacuate several of his comrades who were by now wounded. Moving from position to position, he engaged the enemy at close range until he was mortally wounded. By his unselfish acts of bravery, Pfc. Willett insured the withdrawal of his comrades to the company position, saving their lives at the cost of his life. Pfc. Willett's valorous actions were in keeping with the highest traditions of the U.S. Army and reflect great credit upon himself and the Armed Forces of his country.

Louis Edward Willett was twenty-one years old when he died and he is buried in Saint John Cemetery in Middle Village, New York: Section 037, Row M, Plot 024. His name appears on Panel 15E, Line 37 of the Vietnam Veterans Memorial Wall in Washington DC.