We Now Know Why Cap Didn't Lift Mjolnir In Age Of Ultron
Avengers: Endgame officially confirmed that Captain America (Chris Evans) is worthy of wielding the mighty, mystical Mjolnir — but the film didn't explain why it took so long for the Star-Spangled Avenger to summon the hammer, particularly when he had the opportunity to do just that in Avengers: Age of Ultron. Thanks to new intel from the masterminds behind the film, we finally know why Cap didn't lift Mjolnir until Endgame.
During an AMA (Ask Me Anything) session on Reddit, the Russo Brothers fielded a question about Captain America's ability to wield Mjolnir, the square-headed sledgehammer only able to be utilized by those the Asgardian gods believe is worthy. Its most famous user is, of course, the God of Thunder Thor (Chris Hemsworth). Audiences got the first hint that Captain America would be worthy of wielding the weapon in Avengers: Age of Ultron, when Thor invited the rest of the Avengers to try their hand at lifting Mjolnir. Hawkeye (Jeremy Renner), Iron Man (Robert Downey Jr.), War Machine (Don Cheadle), and Bruce Banner (Mark Ruffalo) all tried and failed to make Mjolnir move — but when Steve Rogers stepped up to the plate, he was able to shift the hammer slightly. This caused Thor to perk up in his seat and look visibly concerned that Steve would genuinely end up swinging Mjolnir through the air. When Steve gave up, Thor breathed a sigh of relief and let out a satisfied laugh.
In Avengers: Endgame, when Captain America summons Mjolnir during the intense final battle against Thanos (Josh Brolin), Thor proudly shouts out, "I knew it!" This suggested that the God of Thunder had known for years that Cap was worthy of wielding the hammer — likely recognizing that fact way back in Avengers: Age of Ultron. It subsequently caused many, including Reddit user @GeneralBenKenobi, to wonder whether Captain America could always wield Mjolnir (and was thus able to lift it in Age of Ultron and simply decided not to), or if he accrued worthiness over time.
Anthony Russo detailed on Reddit that Captain America "always could" pick up Mjolnir, and realized that in Age of Ultron. The reason why he didn't go through with lifting the hammer upon that revelation was because he wanted to spare Thor any embarrassment. As Anthony explained, "Our interpretation of the famous scene in Ultron was that when he realized he could pick up Mjolnir he quickly chose not to, because he didn't want to embarrass Thor."
Why might Thor be embarrassed by his fellow Avenger picking up and putting to use his famous weapon, you ask? Well, it's probably down to the fact that anyone deemed worthy enough to wield Mjolnir instantly obtains all the powers Thor has — flight, weather and electricity manipulation, and inter-dimensional transportation — when they lift it. Combine the abilities Mjolnir grants its users with Captain America's super-strength, durability, and near-indestructible Vibranium shield (that was only chipped away at in Endgame because Thanos' blade is made from something stronger than Vibranium), and it's easy to see why Thor might have gone red in the face if Cap lifted Mjolnir in Age of Ultron. Plus, there's the issue of Thor making a big deal about being the so-called chosen one, not an Earthly mortal like the rest of the Avengers but a god from another realm. We get it, watching a human (a genetically altered human, but a human all the same) lift the ultra-exclusive weapon after you made a show of yourself probably would have been embarrassing.
Cap was sweet to save his Mjolnir-wielding moment for Avengers: Endgame, since it had much more emotional heft and caused Thor to be joyful instead of embarrassed. There was a huge payoff in hearing Thor proclaim "I knew it!" and watching Captain America lay the smackdown on Thanos using Mjolnir and his super-shield. The moment was certainly one of the most impactful of the entire film, with audiences around the world cheering in their seats when it happened. Seeing Steve Rogers lift Mjolnir in Avengers: Age of Ultron could have been funnier — Thor would have been proven wrong, the Avengers would pat Steve on the back for being even stronger than they thought, and Tony Stark would probably joke that Steve would soon be vying for the Asgardian kingship — but watching it happen in Avengers: Endgame was infinitely more moving.