I'm pretty sure America doesn't have to give up its world power just to deal with its southern border. If it does, it's going to be a lot weaker on both.
Prioritizing America isn’t weakness it’s a strength. No empire in history lasted long by neglecting its homeland while overextending abroad.
Ukraine isn’t America’s priority or ally, our borders, economy, and strategic position in the Pacific are. Europe is more than capable of handling its own security, and if they aren’t willing to, that’s on them not us.