a potentially very serious development, with possible spillover effects on a wide range of issues beyond the bilateral relationship. It could cast a serious cloud over the push for the resumption of Arab-Israeli peace negotiations -- or it could push Syria to get off the fence and play ball more aggressively with the U.S. and Israel. It could heighten Iraq's Arab isolation, confirming the widespread antipathy among Arab leaders towards Maliki's government and freezing whatever momentum might have existed towards rebuilding Arab ties with Iraq -- or, if resolved through stronger cooperation against insurgents crossing into Iraq, the crisis could create the basis for a stronger and sustainable Iraqi integration into the Arab region. And it could lead to heightened suspicion of the Iranian role -- or, if Iran's call for a meeting of Iraq's neighbors were taken up, become the vehicle for overcoming the regional cold war which Obama's efforts have so fitfully begun to thaw. It's worth American attention.