Administration claims that Iran has been supplying arms to Iraq's Sunni insurgency have never made any sense. Coming soon after Washington initially accused Tehran of arming Shi'ite militias, they have seemed like a weak attempt to remake its case tying the country to attacks on U.S. troops in Iraq — the vast majority of which are carried out by Sunni, not Shi'a, forces.
One of the unshakable foundations of Iranian foreign policy is support for Iraq's Shi'a, who now more than ever are bloody foes of the country's Sunni minority. And if for some unfathomable reason Iran were arming the Sunni insurgency, would it leave behind evidence to implicate itself?
In April 1983 an Iranian surrogate group blew up the American embassy in Beirut. Forensic investigators sifting through the rubble determined with a fair amount of certainty that the bomb maker had inserted explosives inside the firing chain, ensuring a "signature" was not left to tie the attack to Iran. Iran never claimed the attack, the suicide bomber was never named, and if it weren't for a still classified lucky break, we would have had no evidence the Iranians were behind it. It is unlikely in the intervening years Iran lost its touch. It certainly isn't clumsy enough to leave serial numbers or factory markings on weapons going to the Sunni insurgency.
An intel official recently assigned to Baghdad told me he too thought the Administration's claims are ridiculous. Iraq is too chaotic and the insurgency too fragmented — both the Sunni and Shi'a — to determine the origin of arms. The Iranians certainly are arming Shi'a militias, but what happens to the arms once they get to Iraq are anyone's guess. Among other things, Sunni insurgent groups regularly raid Shi'a caches.
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