Second Front The United Nations is covering its rear in the oil for food (search) scandal. And now it's engaged on a second front as new evidence is emerging that a U.N. ambulance was used by Palestinian terrorists for their getaway following an engagement on May 11, in which 6 Israeli soldiers were killed. The Israelis have been making the charge for years that the U.N. and Red Cross have been providing cover for terrorists, with American taxpayers footing some of the bill. But now there's evidence to back up the charge. In video shot by Reuters in Southern Gaza,...