U.S. Agent

U.S. Agent, also known as John Walker, is a fictional character from Marvel Comics. He is a super-soldier similar to Captain America but often portrayed as more morally complex or even problematic. Initially, he is a patriotic soldier enhanced with superhuman abilities through government programs. Over time, U.S. Agent becomes a vigilante figure, sometimes working independently or in opposition to other heroes, due to disagreements or personal motivations. His character explores themes of patriotism, ethics, and the impact of wartime trauma, making him a nuanced figure within the comic universe.