If this "thing" in Iraq goes as it appears to be going, once the sand settles, I may have to add a fifth center of gravity: IranSyriaIraq. Which leads us to Saudi Arabia. One word: terrified.That didn't take long. The (London) Telegraph is reporting that Saudi Arabia is moving 30,000 troops along the Iraqi border, concerned about the spread of "foreign fanaticism," also known as "jihadism" (see below):
Saudi Arabia has sent 30,000 troops to reinforce its long northern desert border after Iraqi troops withdrew from the other side.
Fighters from Islamic State, the jihadist group, and its allies have already seized frontier posts on Iraq's western borders with Syria and Jordan. The southern border with Saudi Arabia, which regards itself as vulnerable to the threat of jihadism, is more than 500 miles long.
Large parts of it are with Anbar province, the centre of Islamic State power in Iraq and now almost entirely under the control either of the group itself or of Sunni Arab tribes that have allied with it.
The last serious incursion into Saudi Arabia also came from Iraq, after Saddam Hussein invaded Kuwait in 1990. Iraqi forces were eventually repelled from the Saudi town of Khafji, the following January, but only after they were attacked from the air by American jets. [The Saudis can assume they cannot count on US air support this time around.]
Since then, the border has been relatively stable and far more concern and attention has been paid to the southern border with Yemen, which is mountainous and hard to control, and where there have been two separate, long-running insurgencies, one jihadist, and one led by a Shia breakaway movement.