The U.S. policy toward Iraq operates as though it is insulated from the buffeting effects of the greater Middle East. The BBC reports Iraqi accusations of Iranian incursions in the Kurdish north. It has always seemed more than less likely that Iran and Turkey would seek to influence envents in post-Saddam Iraq either indirectly through the Kurds in the North (Turkey) or directly with the Shities in the South (Iran).
BBC - Iraq has accused Iranian forces of entering Iraqi territory and shelling Kurdish rebel positions in the north.
Iranian troops bombed border areas near the town of Hajj Umran before crossing into Iraq, the defence ministry in Baghdad said on Sunday.
If Iran leaning groups were to instigate trouble in the Iraqi north among the Kurds would Turkey seek to become engaged?
Elements of the Kurds have been fighting an insurgency of their own for some time against and within Turkey. Some Shiites groups in the Iraqi south are aligned with Shiites in Iran. The proverbial land of Kurdistan is presently split among Turkey, Iraq, and Iran. Ethnic boundaries and ancient borders do not neatly line up with today's political realities and modern maps; many drawn up under international and British guidence in the early part of last century.
Competing enthic, military, and political relationships mean that U.S. operations may serve to upturn and enflame the balance of ethnic and political power in the greater region. If the Sunni/Shiite divisions have manifest into the war with the insurgency in Iraq, consider that the overlapping and competing tensions throughout the Middle East could produce widespread suffering if further destablized. We need to do everything possible to stablize the area, and one way to do that is to remove U.S. troops to beyond the line of fire.
Turkey has a recent history of democracy compared to many other regimes in the area. The pressure to continue to develop along this path is coming from the EU, which maitains that Turkey adopt key measures before being able to join the Union. This is a significant prize and may be enough to prevent Turkey's engagement. It could make the difference in what could turn out to be a developing communal Middle East war; but given the level of international discord with the Iranian reqime, I don't see anything holding Iran back.