Saudi Arabia has increased it's patrols on its long desert border with Iraq. An increasing number of Islamic militants are going to Iraq to fight Americans (or because they believe they are safer than staying in Saudi Arabia and getting caught by the Saudi police.) Syria and Iran also insist they are not allowing Islamic militants to enter Iraq, but this is not true. However, both nations appear to be blocking armed militants from crossing at the official crossing points. But the roadless portions of the border are, as always, largely left alone.
Speaking of militants, there is fear that the Shia militants from Iran, and Sunni (Wahabi) militants from Saudi Arabia and elsewhere, will eventually start attacking each other as they have long done in Pakistan, Afghanistan. Lebanon and other places where Sunnis and Shias live together.