In Marvel's main continuity, Bucky had been Cap's sidekick throughout WWII. When they fell defusing the missile headed for the States, they were both assumed dead. Cap was recovered by the Avengers in the early '60s; nobody had any idea where James "Bucky" Barnes had gone.
Much later, they found that Bucky had in fact been recovered by the USSR, where they used cybernetics and hypnosis to brainwash him into being the Winter Soldier, their perfect assassin. Eventually, Cap found out and freed him; Bucky went into hiding to avoid the KGB.
A couple of years ago, at the end of the Marvel Civil War, Cap was shot dead (only not really, it was a TIME BULLET!
), and Bucky, safe from the KGB as the USSR had collapsed back in '91, emerged to take up the mantle of Captain America.
So to answer your question, it depends. When we first saw the Winter Soldier, he was a bad guy; it was only later that we found out he was a mind-controlled good guy.
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.