Why doesnt the U.S just start taking countrys over?

The outright takeover of another country would be far to risky these days and not in Americas best interest. We're already in too much deep doo doo for the inhumanity we've inflicted on other countries, peoples and cultures including our own. We're still doing it of course although we're trying to be a lot sneakier about it. Whatever individual or group we can get to become backstabbing traitors to their own families and friends to get what we want in another country or even in our own is preferable. God bless America and Happy 4th of July!