The current US solution for Iraq is founded on the belief that it is possible to staunch Iraq's chaos through a political "fix" that involves direct negotiations with Iran. Unfortunately, the truth is more complicated. Iraq's non-state guerrillas aren't mere proxies of Iran. Instead, they are largely autonomous.
First, these groups don't rely upon Iran for their operating income since they can manufacture income through participation in black globalization's multi-trillion dollar economy. A classic example of this is the decentralized and open source marketplace for the transnational smuggling of gasoline. In a June 2006 report, Ali Al Alak (the inspector general of the Iraqi Oil Ministry) detailed how guerrillas and militias were using the calculated disruption of Iraqi pipelines/refineries, the arbitrage of government subsidies for gasoline, and bribes/hijackings/tampering to generate nearly $100 million a month in income from imported gasoline (30% of Iraq's total fuel imports).
Second, this income provides these groups with the ability to fund their own violence. For example, they can purchase weapons from global arms markets (more black globalization) and hire local mercenaries (to fuel the marketplace for IED attacks and hire militiamen). From the perspective of these groups, an Iranian puppet state is as much a threat to their continued existence as a US dominated Iraqi government. Vive le chaos!