In this Sept. 20, 2013, file photo, Filipino Marines and U.S. Marines from the 13th Marine Expeditionary Unit BOXER Amphibious Ready Group based in Okinawa, Japan, drop from a CH-53 Super Stallion helicopter during a joint military exercise called Philippines-U.S. Amphibious Landing Exercise (PHIBLEX) in Ternate, Cavite province, southern Philippines. (AP Photo/Aaron Favila, File)