"There will have to be convincing evidence before we mount an excavation of any spot that could yield remains," said Larry Greer, spokesman for the Pentagon's Prisoner of War and Missing in Action Office.
Government archeologists would probably excavate a small test site first, he said.
James Clayton Johnson never met his uncle, James Bernard Johnson, who died on Tarawa at age 17. But Johnson, who was named for his father's brother, never forgot that young Marine.
Now 60 and living near Noah in the Florida Keys, Johnson learned of the effort to identify the burial sites of his uncle and 541 other missing Marines on Tarawa while researching his uncle's military records online.
More than 990 Marines and 680 sailors died and almost 2,300 were wounded in the three-day battle after the Nov. 20, 1943, invasion, one of the first Pacific amphibious assaults.
Johnson, a veteran who led troops into Cambodia as a 21-year-old Army platoon leader in the Vietnam War, isn't sure having his uncle's body returned would provide closure. "There aren't any open wounds for me that need fixing," he said.
But Johnson wants the world to know about the volunteers committed to preserving the names and stories of thousands of US service members.
"I get pumped up, and I want people to think and look at things like this," he said.
Noah, a commercial pilot and longtime World War II history buff, raised $90,000 for the work by selling rides at air shows and partnering with The American Legion, VFW, and other groups.
Noah and Massachusetts historian Ted Darcy of WFI Research Group reviewed eight burial sites they believe contain US remains. They say the claim is backed by burial rosters, casualty cards, and combat reports; interviews with construction contractors who found human remains at the sites and locals who have found American artifacts; and other information.