Now in the most powerful position in the United States, walk forward when you gain control at the beginning of the mission until you’re stopped by Keith David, who wants you to make a decision. This decision will have no impact on actual gameplay or story, as they are just there for fun, so choose whichever you want.
In fact, there will be two more decisions like this as you walk down this initial hallway, one where you punch someone and another at the end, choosing whether to get excited or not over watching NyteBlayde. There will be a cutscene that follows, with it ending in an alien invasion.
Once you regain control, mash the button that appears to knock the Secret Service off of you, then start going down the hallway, shooting the aliens that get in your way. When you meet up with Asha, go into the office and stock up on weapons, noting that you can carry all of them at once, so get each one.
The rest of the path is fairly linear, where you will be gunning down more aliens while your Cabinet and friends get abducted. When you get outside, however, you’ll hop into a giant cannon and will need to shoot down some alien ships. One button will fire standard shots, while the other fires rockets.
Keep shooting the ships as they come, until they get into a formation, where you just need to shoot them all down. After doing that, a bigger ship will appear, which will crash into the ground in front of you when you shoot it down. You decide to make your own entrance and get into a battle with Zinyak himself. This is just a series of QTEs, so make sure you pay attention when the button prompts appear. Once the battle is over (with you losing), the mission will end.