During the Cold War, the Soviets and the US each vied for supermacy in every area where they might achieve a military advantage over the other. More powerful bombs, better tanks, more effective spacecraft... And superior human beings.
Aloysius Zeroth was willing to go to any lengths if it meant defeating communism. That included the enhancement of human biology through invasive measures. The man who became know as Codename: Soldier volunteered for that procedure, and was one of the few who achieved notable results before the government shut the project down for its low success rates and the severity of its side-effects.
Codename: Soldier was never able to play a part in the Cold War, but he found a fulfilling carrer as a costumed crime-fighter. At least until his life was irredeemably altered for a second time...