For over the past decade, Marvel Studios managed to meticulously craft together 23 films and a bevy of superheroes into one large overarching storyline, now known as the "Infinity Saga." Throughout these films, fans have witnessed some of the greatest relationships. But it was the at-odds relationship between two marquee Avengers, Steve Rogers (aka Captain America played by Chris Evans) and Tony Stark (aka Iron Man played by Robert Downey Jr.), that really throttled the Marvel Cinematic Universe.

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Since meeting for the first time in 2012’s The Avengers, both Rogers and Stark have never really seen eye-to-eye. The animosity between the duo then escalated a few years later during the events of Captain America: Civil War, when the two heroes couldn’t agree on the Sokovia Accords, and Tony learns of the secret Cap’s been keeping from him. So without further ado, below are 10 reasons why Tony Stark and Steve Rogers weren't real friends.

Both Are Alpha Males

Both Tony Stark and Steve Rogers are no doubt alpha males, always trying to be the dominant male presence in The Avengers. Along with always contently competing to be the best, these two could never really get along because of their big egos.

Steve truly believed his way of thinking was right, while Tony could only see his side of things. They never backed down from their own beliefs, thinking their way was the only way, which caused a lot of tension, not only between them but The Avengers as a whole.

Steve Doesn’t Tell Tony About His Parent's Death

Tony looking angry at Steve Rogers in Captain America: Civil War

In order to protect his best friend Bucky, Steve doesn’t tell Tony that he knew Bucky killed his parents while he was brainwashed to act as the Winter Solider. This is clearly some big news to withhold from someone whom you consider a friend.

By not sharing this information with Stark, Steve had already chosen sides. This, of course, leads to a big fight between the trio, the events which unfold in Captain America: Civil War.

Steve Chooses Bucky Over Tony

An image of Captain America and Bucky

The big fight between the trio is a big reason why Steve Rogers and Tony Stark weren’t real friends. On top of the lies and protecting Bucky, Steve chooses to fight against Stark in one of the biggest battles seen between the members of The Avengers.

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As they begin to fight Steve tells Tony, “I’m sorry, Tony. You know I wouldn’t do this if I had any other choice, but he’s my friend.” Tony replies, “So was I.” The fight and conflict between the two didn’t just affect Steve and Tony, it also caused the rest of The Avengers to split apart.

Tony Takes Steve’s Shield

Tony Stark gives Captain America the shield in Avengers Endgame

In Captain America: Civil War, Tony is distraught after finding out that Bucky killed his parents while he was operating as the Winter Soldier. When Steve decides to side with his best friend Bucky, which leads to an all-out war between Iron Man and Captain America, Stark asks Cap to give back his shield.

The shield, of course, is Cap’s signature weapon, which happened to be made by Stark’s father. At the end of the fight, Stark demands he give him back the shield because he doesn’t deserve it.

Too Different

Overall Steve Rogers and Tony Stark are just too different from each other. Besides Steve being old-fashioned, he was born in 1918, and Tony is a futurist, their personalities are completely polar opposite. Even when they first met in The Avengers these two didn’t get along.

As one of the most complex relationships in the Marvel Cinematic Universe, throughout the “Infinity Saga,” their ideologies were constantly clashing.

Always Bickering

Iron Man and Captain America in Avengers

On top of their ideologies always clashing, Rogers and Stark were somehow always bickering with each other. Instead of letting each other just be themselves, they had to add fuel to the flames by constantly pushing each others’ buttons.

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For example in the opening sequence of Avengers: Age of Ultron, Steve reprimands Stark for his use of language when he cried out “Sh*t,” after being hit. Instead of just letting it slide and letting Stark be Stark, Steve has to make a big deal out of it, which carries through the rest of the film.

Don’t Respect Or Trust Each Other

Captain America: Civil War - Cap vs. Iron Man

You don’t have to like each other to work together as a team. However, Steve and Tony don’t even respect each other, which has led to them being one of the most complex duos in the whole of the “Infinity Saga.”

Even with others being part of The Avengers team, Steve and Tony could never move past their conflicts for the better. This just boils down to the fact that they don’t respect each other or each other's ideas. On top of that, they don’t trust each other.

Steve Didn’t Agree With Tony’s Planet-Wide Security System

The Avengers assembling in Avengers: Endgame

In Avengers: Age of Ultron Tony proposed a plan to create a planet-wide security system. This would protect Earth from any future existential threats. Instead of backing Tony up, as any real friend would do, he challenged him and said he shouldn’t do it to keep the people’s freedoms intact.

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Because Tony never got to create this system, Thanos’ decimation ended up wiping out half the planet’s population.

Tony Blames Steve For Thanos’ Snap

After personally being defeated by Thanos and lost in space for a few weeks, Tony Stark returned to Earth after being rescued by Captain Marvel. When he’s reunited with Steve, instead of being happy to see him after all the time that has gone by, he blames him for Thanos’ Snap.

He goes on to tell Steve that the reason why Thanos was successful was that he never allowed Stark to build the planet-wide security system that he proposed in Avengers: Age of Ultron. Stark continued to berate Steve for the loss.

Tony Is Jealous Of Steve

Tony Stark on a spaceship in Avengers: Endgame

While Steve was still frozen in ice after World War I, Tony grew up listening to stories his father Howard Stark would share about Captain America. As a young boy, Stark was exposed to Howard’s admiration for Cap and his sentiments of him being a protector of the weak.

This made growing up hard for Tony, who felt like he had to measure up to his father in addition to fighting off the jealousy he felt from all the attention Captain America was getting over him.

NEXT: MCU: 5 Times Tony Stark And Steve Rogers Were Best Friends (& 5 Times They Were Each Other's Worst Enemy)