He's still trying to. We can thank him for screwing the Shah of Iran and the crap they hand us now. We can also thank him for handing N Korea a reactor. Lord knows what he's doing with Saudi oil money, but he's anti Semetic.
Undermine vs. destroy might be a distinction without a difference but I still think Obunghole is MUCH worse than Carter. Obunghole WANTS to destroy America while Carter's ineptness, naive foreign policy, and irrational hatred for G.W. Bush have unintentionally allowed our enemies to advance against us. (How's that for a run on sentence?)
Obunghole is the first POTUS in my lifetime that I believe sincerely wants what is not good for America. Others have acted against us but not purposefully.