One of Carter's biggest problems is that he was/is a diehard premillennialist. As a result he was so worried about setting off some kind of war in the Middle East that he tiptoed around the Muslims to the point that they had no more fear of him than they did of Obama/Biden. That's basically what caused the Iran hostage crises. His other problem was that those hardened politicians around him took advantage of his naivete. Basically a good man in many ways, just in way over his head.