To me, the only epistemic value of knowing that Michael Gordon says official sources say Iranian-supplied weapons “accounted for a third of the combat deaths suffered by the American-led forces” last month is that whatever the truth of the matter is to establish a theoretical maximum on Iranian culpability in the death of American soldiers. The administration is lying (for them not to be lying would be unprecedented) and Gordon is passing on what his sources tell him.
As a policy matter, looking at the Iranian support issue tends to highlights how pointless it is to get one’s hopes raised by such minor signs of progress as may or may not be thought to exist in Iraq. Iran is charged with supplying a bit more than 100 explosive-formed penetrator bombs to Iraqi militants per month. Iran is also a bit of a rinky-dink third world country. But even they clearly could be providing a lot more weaponry than that were they so inclined. Hezbollah’s armaments are, for example, much more sophisticated than that. If the Iranians ever were to reach the conclusion that the US were in danger of achieving its goals of creating a stable Iraq happy to play host to large US military installations and serve as an anti-Iranian bulwark in the region, Iran could easily step up its assistance and then you’re back to square one.
The issue here, then, really isn’t where, exactly, these EFPs come from and why. The issue is whether you think it serves US interests to try to reach an accommodation with Iran so they we can fight terrorism by trying to fight the al-Qaeda terrorists who want to come here and kill or, or whether you think it serves US interests to continue picking unprovoked fights with tangential adversaries. But before you pick what’s behind door number two, just keep in mind that a US-Iranian escalation cycle will certainly lead things to get much, much worse over the short and medium terms.