Federal air marshals in four major cities will speak out tonight on their local television newscasts to warn the American public about serious flaws in the much-heralded homeland security program. "Our job is to prevent another Sept. 11 from happening. We can’t do that. Not under these circumstances, not under these conditions," says a Las Vegas air marshal in an interview. The air marshal is one of 17 who will appear anonymously in shadow on local ABC affiliates in Denver, Las Vegas, Atlanta and Dallas. The air marshals say that flawed policies put airline passengers in as much, if not more, danger today than on 9/11. On May 19, an ABC News undercover investigation on 20/20 and World News Tonight was the first to reveal how Federal Air Marshal policies may be putting the flying public at risk by making it impossible for air marshals to work undercover. A month later, Federal Air Marshal Service Director Dana Brown announced that employee working groups were reviewing the agency’s policies. But the air marshals appearing on local television tonight say that Congress and the Department of Homeland Security have ignored the concerns of the air marshals for years and have done nothing to fix the problems. "We do not want to come before the media. This is the last hope that we have to get these dangerous policies changed," says an Atlanta air marshal.