The Soviets discovered that they couldn't make ends meet by only enslaving people within their own borders, so they had to take over other nations as well (Estonia, Latvia, etc. etc. etc.)
I'm guessing that an excellent plan such as yours would ultimately not be able to sustain itself, and the Leftists would demand that we invade Canada, as a start.
hmmmmmm......
Invade Canada? That will come. But first we will storm the beaches of Arlington, roll over Mt Vernon, sweep aside Bellingham, and stop at Lynden for the blintzes.