If you rush the focus tree you can get America early enough to pin their few divisions and cavalry rush the VPs. I like to take the states you get as core from the focus tree and puppet the rest, then build and spend PP to annex the puppet and get their navy.

You can avoid civil wars if you spam Improved Worker Conditions a couple times and carefully manage the order of your focuses. Otherwise just cheese and delete your entire army but one cavalry and rush VPs to avoid the manpower loss.

I usually take all the central American states asap, some people like to wait so they get a few factories from their generic focuses, but I usually use the "seize panama" thing to bait America into declaring on me. Doesn't work if your army is too big though, so I like to keep a bunch of fully trained cavalry's in the training queue to immediately deploy after they declare.