Resources is still hella limited compared to average US consumption. Especially when you consider extraction costs; which will continue to grow and quite severely at that.
Cutting off trade is more or less cutting off your nose to spite your face; there's really no good reason for it aside from nationalistic impulse of not having to relay on other parts of the world. As well, you're doing damage to the people who sell to us by killing their markets. While finding a solution is certainly necessary, kneecapping yourself will hardly help with that.
Ironically enough, the easiest and most effective answer is pretty much something Lenin, or at least Gorbachev, would agree with: Direct government interdiction; a la the development of Space Travel in the 50's and 60's.