In simple terms, the forces dividing Iraq have two major regional clients: the Sunnis have Saudi Arabia, and the Shiia have Iran. The current Iraqi government is majority Shiia. In its stunning wisdom, the Bush Assministration has chosen to arm the "former" Sunni insurgents in Iraq, as the current Shiia-dominated government (Prime Minister Maliki, ostensibly supported by Dumbya) rejects the Sunnis' demands for political redress. Expected outcome? Intensified sectarian violence, with Saudi Arabia and Iran as the drivers.
It's clear that the Bush Assministration has been listening closely to the "counsel" of the Saudi Government/"Bandar Bush" of late, especially with the looming $30 billion arms deal in the works with the Saudis. Bidness, Texas-style. National security, Saudi-style.