One line from the first Iron Man correctly predicts Captain America's (Steve Rogers) biggest fear. Directed by Jon Favreau, the 2008 blockbuster introduced Robert Downey Jr.'s Tony Stark and proceeded to lay the groundwork for the MCU. While much of Iron Man's subsequent arc leading to his foreshadowed death in Avengers: Endgame, one particular piece of dialog from its titular character foreshadowed the one thing that Steve Rogers dreaded.

During the events of Iron Man, Steve was still frozen in ice, as it wouldn't be until a couple more years before he was found and awoken in modern times. So, at this point, Tony has no knowledge of the Star-Spangled Avenger other than public information and what he'd learned from his father, Howard Stark (John Slattery) from their time working together during World War II. Tony and Steve's first encounter was aboard the SHIELD Helicarrier in the middle of The Avengers. Despite this, the genius billionaire was able to accidentally foretell what would later be revealed to be Captain America's worst fear.

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The original Iron Man film with Robert Downey Jr. opened with Tony's road trip in Afghanistan as he traveled to inaugurate his newest creation — the Jericho missile. During his ride with some service members just before they were ambushed, one soldier asked for a photo. He complied but made a quip about the peace sign that the military serviceman made, saying: "Peace. I love peace. I'd be out of a job with peace." At this point, this partially rang true; after all, he's an arm's dealer. But after his abduction, he didn't have any problems shutting down their weapons department, shifting their focus on other branches of their business. Instead, this particular line is more applicable to Steve, who's a war soldier. While Captain America was all for a conflict-free world, he knew nothing else but to enforce peace. So if it comes naturally, he'd be the one out of a job.

Peggy as she comes up to Steve for a dance in Avengers Age of Ultron

Incidentally, Steve having this imperfect flaw and fear was confirmed in Avengers: Age of Ultron. During the team's Johannesburg mission to confront Ultron (James Spader), almost every hero was hypnotized by Scarlet Witch (Elizabeth Olsen). As previously seen with Tony in Sokovia, Wanda Maximoff's spell showed them the things they were most afraid of. For Captain America, that's returning to the '40s and learning that the war is over. Interestingly, this didn't seem like a bad thing, especially since it meant that he and Peggy (Hayley Atwell) can finally be together. But, it actually revealed that Steve's frightened of being useless in a time of peace. As the Star-Spangled Avenger was created to be a soldier at the height of World War II, he'd been operating as the protector of the oppressed and enforcer of justice. But all of that would be gone if there's no looming threat to the public.

Given all this, it's curious how Steve lived a quiet retired life at the end of Avengers: Endgame. Perhaps by then, he realized that he'd done his part to ensure that peace of the universe and it was time for him to put himself first. Still, considering their difference in background and demeanor, it's interesting that Tony's line from Iron Man which was supposed to be about him turned out to be more applicable to Captain America.

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