(NEWSER) - Tension between Arabs and Kurds, rather than the usual friction between Sunnis and Shia, has become the greatest threat to Iraqi security, says the top US general in the country. The oil-rich Kurdish region has become "the No. 1 driver of instability," Ray Odierno told reporters yesterday, and "many insurgent groups are trying to exploit the tensions." The Kurds are battling Baghdad over who has control of oil reserves, and support for an independent Kurdistan is rising. More»