[BenLurkin]

However, it is unclear whether Iran has slowed shipments of the deadly weapons into Iraq or not,

What could be the reason for Iran slowing shipments of these weapons (if indeed they are slowing the shipment)?

Or are our forces simply doing a better job of sealing off the supply lines form Iran to its operatives in Iraq?

[edsheppa]

What could be the reason for Iran slowing shipments of these weapons (if indeed they are slowing the shipment)?

According to reports I read on FR, Quds operatives in Iraq were pulled out a few months ago out of fear that they'd be captured in Surge operations. I think this accounts for the dramatic decrease in violence at that time (i.e. there was never a civil war). And it could also account for fewer weapons from Iran - no Quds to manage the Iraqi side of the supply line.