IRAN’S BOMBS….Spencer Ackerman runs down the various possibilities for how and why Iranian explosives have been found in Iraq:

Any number of alternative explanations are possible: renegade Qods Forces could be trying to make money on the lucrative Iraqi black market for weapons. Iran could simply be arming its Shiite proxies in the civil war as opposed to seeking attacks on U.S. forces. And those proxies could in turn be unloading some of the weapons on the very active black market. (Remember, some of them were discovered in December at a compound belonging to U.S. “partner” SCIRI.) An element of the Qods Forces could be attempting to attack U.S. forces without the knowledge of their leadership. And so on. These are contending theories that require additional information to be compelling. And there should be some explanation of why most of the deaths of US forces from these IEDs are coming from Sunni insurgents who are opposed to the people Iran supports — a fact that some believe points to the black market.

This last point seems like the most important one to me. It’s certainly possible that the radical Shiite mullahs of Iran are supplying weapons to the radical Sunni insurgents of Iraq, but it’s unlikely enough that, at the very least, it should raise some healthy skepticism about the whole story. The Iranian leadership might eventually turn out to be up to its ears in this — though even Bush is unwilling to flatly say so at the moment — but so far the evidence is thin. Wait and see.