Captain America ... supervillain? Marvel fans are fighting back against the star spangled traitor.

It was the “Hail Hydra” heard ‘round the comic world.

It’s one thing for the villainous Arnim Zola or Hive or Dr. Faustus to swear their allegiance to the former Nazi organization. But when it’s uttered by Steve Rogers’ Captain America, all bets are off.

That’s the backstory to the latest Marvel Comics’ event, “Secret Empire.” Secretly recreated by the evil Red Skull using a cosmic cube, Cap has engineered Hydra’s takeover of the United States. The first issue, out this week, has most of our heroes trapped in space or a dimensional bubble around New York City.

This kind of transformational setup for major events is commonplace in comicdom. This time, there’s something different – and it’s gotten under some people’s skin.

This isn’t the typical Marvel event where the downtrodden heroes must pull themselves up by their bootstraps to take on the robotic Ultron or the shapeshifting Skrulls. No, now they’re facing one of their own. Their most trust ally. An American icon.

Literally.

Captain America is the supreme ruler of Hydra, and therefore the U.S. as well. While still maintaining his Boy Scout-like integrity, the star-spangled Avenger casually approves pumping mind-altering drugs into the water supply. He even orders – then oversees – the execution of one of his most trusted allies.

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You can understand why some people are bent out of shape. Maybe. There was an outcry when Doctor Octopus “killed” Peter Parker and became the Superior Spider-Man. After Superman died (the most recent time), Lex Luthor stepped into his heroic boots.

But this time it’s different. It’s Captain America.

America.

At the C2E2 conference last month, a U.S. military veteran confronted the Secret Empire creative team, including writer Nick Spencer. She questioned why they were demonizing Cap – whose comics exploits were sent to soldiers overseas.

She said it felt like a betrayal.

To be sure, putting the Sentinel of Liberty in the hands of former Nazis is bound to stir up some controversy. It would be easy to simply write off this latest move as a publicity stunt. But even if that’s all that it was, the situation has clearly struck a chord with readers in this politically charged time.

The controversy reached such a high volume that Marvel issued a statement Wednesday. It read, in part, “At Marvel, we want to assure all of our fans that we hear your concerns about aligning Captain America with Hydra and we politely ask you to allow the story to unfold before coming to any conclusion.”

Spencer and the creative team at C2E2 promised that the story line has been in the works for two years – long before the presidential election – or even the primaries – was decided.

Although some Marvel books have touched on politics, even depicting a Donald Trump-like villain (completed with “Make America Great Again”) in a story last year. And many of the publisher’s creative team have taken to social media expressing their outrage over President Trump and his policies.

Whatever the case, Cap’s greatest asset – his integrity – may end up getting in the way of his artists being able to tell a compelling story about him.