Who Will U.S. Special Forces Report To In Iraq?

I'm curious, based on two articles I just saw. Obama is planning on sending 275 U.S. Military personnel to Iraq "for the purpose of protecting US citizens and property, if necessary, and is equipped for combat". He conveyed his intentions in a letter to the U.S. Congress.

In a separate article, there's this from the AP: Iran's general in Iraq, militants seize key city:

In a sign of Iran's deepening involvement in the Iraqi crisis, the commander of Tehran's elite Quds Force is helping Iraq's military and Shiite militias gear up to fight the Sunni insurgents advancing across the country, officials said Monday.

My question is this: if John Kerry has already announced the United States' willingness to engage Iran on the defense of Iraq, how will that collaboration manifest itself? Hmmm?