PRESIDENT Obama says the noose is tightening around Col. Muammar el-Qaddafi. In fact, it is tightening around the Libyan rebels, as Colonel Qaddafi makes the most of the world’s dithering and steadily retakes rebel-held towns. The United States and Europe are temporizing on a no-flight zone while the Organization of the Islamic Conference, the Gulf Cooperation Council and now the Arab Leauge have all called on the United Nations Security Council to authorize one. Opponents of a no-flight zone have put forth five main arguments, none of which, on close examination, hold up.