The Air Transport Association (ATA), the industry trade organization representing leading U.S. airlines, today reminded passengers of new and more restrictive travel document policies set to take effect in early 2007 for all travelers entering or re-entering the United States by air from any part of the Western Hemisphere.Beginning Jan. 23, 2007, all travelers will be required to present a passport to enter or re-enter the United States, including U.S. citizens returning to the U.S. by air from Canada, Mexico, Central and South America, the Caribbean and Bermuda.Find the details here.