The season premiere of Supergirl season 4 has launched the Girl of Steel into a nightmare scenario she could never have imagined, as a wave of hate threatens to undo everything Kara has accomplished over the last three years. The United States has been plunged into a constitutional crisis with the revelation that the president is an alien, and now hate groups are ascendant.

Supergirl has always tended to wear its politics on its cape, and that's clearly going to be the case with season 4 as well; it's not hard to see the political commentary in this plot. But another fantastical element has been added into the mix with the introduction of some sort of Kara doppelganger, a twist inspired by the Superman: Red Son Elseworlds comic.

Related: Supergirl Season 4: Cast & Guest Star Guide

Like all the best premieres, this episode lays the foundation for everything that's going to follow. So here's our run-through of all the key questions we're likely to see explored from this point.

11. The President Has Been Outed As An Alien - What's Next?

Previous seasons of Supergirl had introduced viewers to President Olivia Marsdin, a powerful pro-alien politician. Marsdin was personally responsible for pushing the Alien Amnesty Act, granting extraterrestrials the rights of United States citizens. But Kara swiftly learned that Marsdin is actually an alien herself, a shape-shifting Durlan who was determined to ensure Earth didn't suffer the same fate as her homeworld.

Now the secret is out and the whole world knows that President Marsdin isn't human. We can expect her presidency to be challenged, and everything she's done to be called into question - including the Alien Amnesty Act. Hate groups will be able to argue that aliens have only become seen as acceptable because they infiltrated even the highest echelons of political power. Conspiracy theories will run rampant. And the world will become a very dangerous place for aliens.

10. Will The Alien Amnesty Act Be Revoked?

Supergirl Aliens

A constitutional crisis will inevitably grip the United States in the wake of the Supergirl season 4 premiere, and the Alien Amnesty Act will be challenged. There'll no doubt be an intense political debate about whether or not this Act should be revoked, and that will generate a lot of air-time for prejudice and bigotry. Should the Act actually be revoked, everything President Marsdin has fought for will be undone, and we'll see a dramatic upsurge in hate crimes against extraterrestrials. Kara will find her optimistic nature challenged like never before.

Related: A Complete Guide to Supergirl's Aliens

9. Is Supergirl Season 4 Deliberately Evoking the X-Men Comics?

Ultimate X-Men Comic

Supergirl season 4 will feel oddly familiar to fans of the X-Men franchise; it's using the idea of aliens as a repressed minority, a group who are feared because they're unlike us, with hate groups working to torture or kill them. It's not hard to spot all the same story beats the X-Men comics traditionally associate with mutants, the most explicit being a discussion of the ethics of using an image inducer. The X-Men have faced that same debate several times, with some mutants - like Beast and Nightcrawler - using holographic disguises to appear normal, but questioning why the world won't accept them as they are. It's surprising to see the idea reproduced so faithfully on a DCTV show.

How far will Supergirl season 4 choose to take things? Depending on how bad things get, it's not inconceivable we could see an "Alien Registration Act" requiring all extraterrestrials to register with the United States Government. That would place even the likes of Kara and her cousin in real difficulty.

8. Just How Big Is The Anti-Alien Movement?

The anti-alien movement in Supergirl is clearly far bigger than anyone believed - and it seems to be global in scale. One character has been forced to leave England because they got tired of prejudice, for example. And when Kara stumbles upon the Graves' servers, she realizes that there's a vast network of people across the globe, all encouraging one another to hate, blaming the aliens for their own problems and even plotting murders. Kara is rightly horrified; but as big and well-organized as these groups already are, the fact they successfully exposed the President is going to give them a major recruiting boost.

Related: Supergirl Takes The First Step In Introducing Darkseid To The Arrowverse

7. Is Lex Luthor Really The Mastermind?

We've heard a lot about Supergirl's Lex Luthor over the years, but the season 4 premiere raised some dangerous questions about him. We were told that Luthor was betrayed by his head of security, Mercy Graves, and that she turned state evidence against him; that led to Luthor's incarceration, and he's currently in jail serving 32 consecutive life sentences. Curiously, though, Lex's mother apparently scooped Mercy up as an employee straight after - hardly behavior you'd expect for someone who'd just betrayed her son. This situation is all the stranger given that, in the comics, Mercy is incredibly loyal to Lex. The idea of her turning state evidence is unprecedented.

Related: Lex Luthor Is The Master of DC's Future Universe

So is it possible that Lex Luthor is in jail because he wanted to be there? It's not hard to imagine a scenario where Lex realized he was becoming a little too notorious, and thus arranged for himself to be imprisoned. Now he's in jail, he's free to put his plans into action with impunity, confident that nobody will think to look at him. Lex could easily be the mastermind behind the various anti-alien factions Kara has confronted over the years; it's surely not a coincidence that they've often had ties to Lex, or to his technology.

Page 2 of 2: More Supergirl Season 4 Premiere Questions, From Guardian to Martian Manhunter

6. Could Bruno Mannheim Lead To Intergang?

In the Supergirl season 4 premiere, Lena struck a deal with the DA in order to get James off the hook - but it might come back to bite her. She's presented evidence to the DA that will enable charges for money laundering to be pressed against Lex's old partner Bruno Mannheim. In the comics, Mannheim is traditionally tied to the criminal organization known as Intergang, one of the most dangerous crime empires in the world - a threat that's even given Superman pause. Lena may have just placed herself in Intergang's crosshairs.

5. Why is Guardian So Unpopular?

Jimmy Olsen as Guardian in Supergirl

On the subject of Guardian, it's interesting to see that National City has reacted very differently to the masked vigilante than they have to Supergirl. Technically both have kept a secret identity, and only James has gone public with his. So why has the public embraced Supergirl, but apparently rejected Guardian? There are two possible answers. The first is that James's decision to wear a mask suggests to the world that he has something to hide. The second, and more likely, is the problem of race. Back in season 3, James admitted that hates the fact that people will just assume a black guy is up to no good. It's the kind of political topic Supergirl has always confronted head-on.

Related: Supergirl: Why Superhero Jimmy Olsen Doesn't Work

4. Why Hasn't Kara Been Spending Any Time With J'onn?

One of the strangest things in the Supergirl season 4 premiere is that Kara hasn't spent much time with J'onn since he left the DEO. J'onn has become like family to Kara and Alex over the last three years, and yet it seems that his decision to explore a new path has meant they've pretty much cut him out of their lives. When Supergirl does cross paths with J'onn, she does her level best to ignore everything he's saying, which is a pretty odd attitude for someone she considered a mentor. The only explanation that makes sense is that Kara disagreed with J'onn's decision to leave the DEO, and hasn't been able to forgive him for it.

3. Has Kara's Optimism Crossed The Line To Willful Blindness?

The Supergirl season 4 premiere really doesn't show Kara at her best. She closes her eyes to key hate crimes, ignoring J'onn's warnings and insisting she herself feels nothing but love and appreciation. Kara is convinced the country has turned a corner; even Alex seems more than a little stunned at just how insistent she is about that, but chooses not to push the issue with her strong-willed sister. Supergirl's eventual explanation is a fascinating, albeit bizarre, one. She essentially explains that she's clinging on to her optimism in the face of all the facts, desperately attempting to believe that the world isn't as dark as she fears it is. That's a false optimism; frankly, it's more like willful blindness. True optimism comes from facing all the evil and ugliness of the world head-on, and yet still believing good can triumph.

2. Why Doesn't Kara Take Backup To The Warehouse?

Supergirl Season 4 Trailer

Sadly, the Supergirl season 4 premiere also doesn't show Kara at her brightest. In her first meeting with the Graves siblings, she learns that they've prepared for her; they have weapons that she simply can't overcome, and they successfully restrain her. And yet, when new series regular Brainiac-5 finally locates their base, Supergirl heads off to check out the warehouse on her own. She doesn't bother asking for backup. It could just be overconfidence; more likely it's foolishness. Kara can count herself fortunate she didn't wind up captured - or worse.

1. What's Going On In Kasnia?

The Supergirl season 4 premiere episode comes to a close with what seems to be a Russian invasion of Kasnia, with the mysterious Supergirl doppelganger at the head. Again, the idea of Russian expansionism is a very political one - and just the kind of topic you'd expect Supergirl to tackle. We can assume that Russia will take advantage of the political turmoil in the United States, continuing their expansion as quickly as possible. But how will Kara take it when she sees the Russian military is being led by someone who looks just like her?

More: Elseworlds: Everything You Need To Know About The Arrowverse Crossover