This, bolstered in the face of the fact that we would not have to waste American lives, and likely very few Canadian and Mexican lives apart from the ones strategically necessary to instill American order and righteous justice. That's because we possess nuclear weapons, and these nations do not. How fitting. So all we need to do, or rather the government if they'd listen, is threaten to nuke the major cities of Canada and Mexico unless they render their unconditional surrender to us. Unless they were crazed beyond the rote I see them to be, they will surrender. And if they don't the obliteration of one major city to save the rest of the good people of that nation will be a commendable sacrifice to be remembered.

Therefore in some sense the phrase "invade" the countries is a bit of a slogan, although an illustrative one. We don't need to engage in the horrible affair of prolonged or direct warfare. We obtain their joyous surrender, we instill justice by making executive moves, and we prosper.