It won't be without cost, but I doubt we would lose. Their army is basically useless. Their navy is formidable, but inexperienced (and the training levels are unknown). On paper, the Russian navy was formidable, but in reality we discovered it really wasn't. Those are big question marks with the Chinese navy. We have vastly more experience with aircraft carriers than they do (and a lot more of them). So their new carriers are also a question mark.

Not that we should underestimate them. That is always a mistake. But if we have competent leadership (which, right now, at least on the political side, we don't), it is far from a foregone conclusion that we would lose.

Also, that's just us. There is still Japan, Australia, the UK, and really all of NATO (though many members have no navy, or at least no blue water navy). With all of that arrayed against them, I doubt that they could win.