You may have heard that Captain America is… different now. It might seem that the change is coming out of nowhere, but it probably not.
Born on 4 July 1918, Steve Rogers is the first man to be called Captain America. The Super-Soldier Serum that made him a peak physical specimen during World War II also kept him youthful. But when a villain in a 2014 storyline drained the Super-Soldier Serum from Steve Rogers' body, he aged decades in an instant and became too feeble to wield his shield.
Steve then passed the red-white-and-blue costume to his friend and partner Sam Wilson, who previously fought bad guys as the Falcon. Sam's tenure as the new Cap has been controversial in the real world and in the Marvel Universe. Despite a recent falling out between the two former partners, both men wound up working together to investigate SHIELD's use of Cosmic Cube fragments to brainwash supervillains in the sleepy suburb of Pleasant Hill.
These fragments became self-aware in the form of a four-year-old girl called Kobik, who used her powers to make Steve young and buff again. In the Avengers Standoff crossover, Bucky, Steve and Sam — who've all been Captain America at one point — fought alongside various Avengers squads to capture the supervillains who were violently revolting against what was done to them. In the beginning of that storyline, Kobik zapped Steve with her powers. It looked like a playful moment but could actually have been the start of something sinister.
The first issue of Steve's new comic shows never-before-seen moments from his past, where it seems like he's being recruited in Hydra, the evil terrorist organisation who are pretty much Nazis.
Remember, Cosmic Cubes have almost always been used by villains who wanted to reshape reality and rule the world and blah, blah, blah.
Even though she seems to be an innocent little girl, Kobik is made of pieces of different Cosmic Cubes, some of which might still have the imprint of the bad guys who used them. In the first issue of Thunderbolts — a team of reforming villains who were inmates in Pleasant Hill — several sequences make it clear that she doesn't have a grip on the consequences and moral implications of her enormous power.
Later in Thunderbolts #1, Bucky and Moonstone argue over leadership of the team and the more powerful villainess says that whoever takes the stone from her body can be top dog.
It's possible that some villainous influence from previous Cosmic Cube users may be screwing with Kobik's preschool sense of proportion and right and wrong. Little kids already don't have much grasp on that stuff but a child grown from remnants of galactic artefacts used mainly for evil might have even less.
Whatever twisted legacy has worked its way into Kobik's head may have led her to pervert Steve Rogers' memories and turn him into a Captain America that says "Hail Hydra." Steve even says he feels like a stranger in his own body. Of course, there could be another reason, like the telepathic powers that the Red Skull gained from stealing Professor X's brain — this is superhero comics, after all — but a messed-up preschooler with Cosmic Cube powers seems like a very likely culprit.