We have no Constitutional authority to invade countries with murderous dictators anyway. RP is not against war, but he's against pointless, undeclared wars. This is why veterans support him overwhelmingly. Who funds the other candidates? The biggest lobbyists around, big energy and big banks. If we're going to have more wars, they must be declared as the law mandates. Then again, we're broke.
The "we'll just trade with them" is actually how our foreign policy must become. We do not meddle in other countries' affairs. We can't afford to be the world's police any more. I like how the other GOP candidates are so excited for potential war with Iran even though they have no nukes, whereas countries such as India, Pakistan, and Saudi Arabia have had nukes for a while.
If you (generally speaking) are pissed about genocide in [insert third world garbage hole here], then travel there and buy some guns. We have zero obligation to anyone but ourselves. Ron Paul has said countless times that he is for defense, not offense, and that we'd probably have more military bases on our soil than in other areas around the world.
And yea, we're broke!
It all comes down to the Israel influence. They have plenty of nukes and can defend themselves (even Netanyahu said this himself in many speeches). I'm sick of Santorum, Gingrich, and Romney treating them like our 51st state.