Ignatius in the WaPo, here
"...A disturbing test of Iran's missile technology and the robustness of its command-and-control systems came in the war in Lebanon in the summer of 2006. Tehran's proxy army, Hezbollah, was able to keep firing its Iranian-supplied missiles at Israeli population centers despite several weeks of aggressive Israeli attacks....It's impossible to say whether Iran's march toward nuclear-weapons capability could have been stopped by diplomacy. But there hasn't yet been a good test. Because of bitter infighting in the Bush administration, its diplomatic efforts were late in coming and, once launched, have been ineffective. Iran ... views America as an aggressive adversary that wants regime change, no matter what Washington says..."