"starting to..." I've got a clue bat for ya, they're already here. Most of the big cities are a total loss. The colleges and universities are just old school reeducation camps of left wing loonies. The major charities and funds are run by Progressives (sic) who are anything but. The federal, state, and most local governments are infested with lefties and Progressives.
For reference, read Fall of the Roman Empire.