USians BTFO

You know what you must do next.

I mean yeah it's vulnerable in general just having the capital on the coast, but the AI will like send an army to the Dixie HQ to stop an invasion (drawing it away from another front!) but if you cancel the invasion they'll redeploy to a front, giving you a couple weeks to invade unopposed as long as they don't have extra armies (which they won't if they're busy fighting the French or British). There's no penalty to canceling a naval invasion apparently, you can immediately restart it the next day

The secret to killing the USA early is to zerg them with rapid advance cavalry stacks, they only start with 10 regiments so you can crush them into dust easily. Always take Pennsylvania and New York, they're dead without them

I've been able to take them out early with all sorts of minor powers with this strat. One time I annexed or puppeted all of the USA as China by 1855

Otherwise they're like Russia and Ingria where you can just neuter a massive superpower in a couple months.

Literally why I move the capital to Moscow every time I play as the Russian empire. Used to also be because under the old military system uncored provinces never sided with factional revolts and could be used as military-industrial belts to prop your government up during a fierce Civil War that has you facing off against all cored provinces then downgrading their military bases and conscription centers all the way to irregular infantry before the civil war event fires to weaken their military power and then steamrolling them as soon as you're given the green light to do so

So it's worked for me because it really fucks up the US AI. They can't figure out where to put their armies. As long as the British fleet will help you enough that the U.S. can't send ships to the Dixie sea node, you can basically naval invade Alabama for free. Just pay attention to the Naval Invasion indicator and when it shows that the U.S. has an army stationed in that HQ, cancel the invasion. If the war is close enough on the other fronts, i.e. you have the British and your main army occupying them in the midwest, the AI might send an army to station it to fight a naval invasion, but if you cancel the invasion they'll usually send the army back to the front. Once there's no armies in that HQ, there's no resistance for the invasion, as long as you don't have to fight their ships.

I kinda fucked up in the war strategy this run by taking New York, I thought it'd be good to build up and steal their GDP but it's just fucking radical city, nothing I build will raise their SOL, and it opens up two additional fronts in the north which the U.S. can easily throw armies at but which as Mexico, even with allies, I can't really do that.

p.s. Unless your armies can beat them 1v1 it's important to do hit and run shit, once the U.S. sends an army to stop your invasion force after it's taken a state, start another naval invasion in the same HQ as long as there's no ships or armies stationed in that HQ. Like take Alabama, and the day before they deploy to the front, naval invade florida to expand the front without having to fight them

You don't, if that happens you're fucked. You could ally with France and hope for the best, but that's probably not good enough to overcome a US/UK alliance. The way to beat the US as mexico is to get yourself a European ally, build up heavily and abuse the naval mechanics.