A Retreat Under Fire 
 
 Chief Slabinski’s team was ordered to establish an observation post on top of the mountain, Takur Ghar, during Operation Anaconda, an effort to encircle and destroy Qaeda forces in the Shah-i-Kot Valley in eastern Afghanistan, about 25 miles from Pakistan. The battle occurred less than three months after bin Laden had escaped at Tora Bora, and American commanders still hoped to capture or kill senior Qaeda leaders. 
 
 Chief Slabinski’s plan was to land by helicopter near the base of the 10,000-foot mountain around midnight and climb up stealthily, but a series of delays involving aircraft left no time to do that before dawn. Under pressure from superiors, he said, he reluctantly flew to the peak at about 3 a.m. 
 
 Unbeknown to the SEALs, Qaeda forces were already there, and they hit the helicopter with heavy fire. One of Chief Slabinski’s men, Petty Officer First Class Neil C. Roberts, fell out about 10 feet above the ground, and the pilot could not retrieve him before the stricken aircraft crash-landed a few miles away. 
 
 Shortly before 5 a.m., the five remaining SEALs and Sergeant Chapman returned to the top — later called “Roberts Ridge” — on another helicopter to try to rescue Petty Officer Roberts. They did not know that enemy fighters had already killed and tried to decapitate him. 
 
 The Americans were again met by a withering barrage. Rushing through thigh-deep snow, Sergeant Chapman charged ahead of Chief Slabinski, and they killed two fighters in a bunker — a hole dug in the ground under a tree — before the airman was wounded. 
 
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 Under fire, the SEALs retreated about 15 minutes later. Chief Slabinski’s plan, he said, was to take cover and let a circling Air Force gunship hammer the Qaeda fighters before trying again to seize the peak and recover Sergeant Chapman’s body. 
 
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 But grenades and mortar fire drove the SEALs farther down the mountain, making it impossible to return. Three Army Rangers, an Army helicopter crewman and another Air Force commando were killed later that morning after arriving as reinforcements. 
 
 Almost as soon as the guns fell silent, the accusations started to fly. Some Ranger, Army Special Operations aviation and Air Force special tactics personnel blamed the SEALs for their losses. 
 
 Soon after, the military opened an investigation to determine what had gone wrong. The chief investigator, Lt. Col. Andrew Milani of the Army, wrote later that an Air Force gunship had failed to detect the militants on the mountaintop and that the SEALs had “violated a basic tenet of reconnaissance” by landing directly on their observation post instead of hiking up to it. 
 
 Colonel Milani also looked into footage captured by a Predator drone about 50 minutes after the SEALs had left the mountaintop. The grainy images showed someone in the bunker defending himself against two attackers and killing one with a rifle shot, prompting the question: Who was that? 
 
 Colonel Milani’s investigation remains classified, but an unclassified paper that he wrote in 2003 offered two possible explanations: The Qaeda fighters had become confused and were firing at one another, or Sergeant Chapman, still alive, had resumed fighting. The colonel did not reach a conclusion, based on the evidence he had. But the suggestion that members of one of the military’s most elite Special Operations units might have, even unintentionally, left someone from another service to fight and die alone added to the tensions. 
 
 Sergeant Chapman, a father of two daughters, in 2003 was posthumously awarded an Air Force Cross, a recognition of valor second only to the Medal of Honor, for his initial charge atop the mountain. The citation noted that Chief Slabinski, who received a Navy Cross for his actions in the firefight, had credited the airman “unequivocally with saving the lives of the entire rescue team.” 
 
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 Sergeant Chapman had enlisted in the Air Force as a computer technician, but soon found that he was not suited to a sedentary lifestyle. A former high school diving and soccer star from Windsor Locks, Conn., he transferred into the elite ranks of the Air Force Special Operations Command as a combat controller, a job that involved calling in airstrikes and handling radio communications for SEAL Team 6 and other secretive units. 
 
 By the time he had joined Chief Slabinski’s team in October 2001, he had spent more than a decade in Special Operations and, at 36, was expressing doubts about his ability to keep up, Chief Slabinski said. The chief told him that he had nothing to worry about. 
 
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 New View of a Battle 
 
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 Sergeant Chapman was considered for the Medal of Honor when the secretary of the Air Force, Deborah Lee James, directed the service’s Special Operations Command to review the seven Air Force Crosses awarded since the Sept. 11, 2001, attacks for possible upgrades. She recently recommended the award to the defense secretary, whose approval is required before it goes to the White House. 
 
 Pentagon policy forbids military officials to talk about potential Medals of Honor, but several officials, speaking only on the condition of anonymity, said that even the sergeant’s initial bravery had stood out. 
 
 Chief Slabinski said he wondered whether the Air Force was motivated as much by hopes of receiving its first Medal of Honor since the Vietnam War as by a desire to fully understand what transpired on the mountain. (Since the Sept. 11 attacks, 12 Army soldiers, three Marines and three SEALs have received the medal for gallantry in Iraq or Afghanistan.) 
 
 A briefing prepared by Air Force special operations officials dismisses as “not viable” Colonel Milani’s suggestion that the gunfight caught on video by the C.I.A. Predator might have involved militants fighting one another, according to people who have received it. That the airman was alive and fighting “is fully supported by the evidence,” the briefing slides state. 
 
 The use of the imagery-enhancement technology to scrutinize the Predator video was central to the findings, particularly when combined with footage, from an AC-130 gunship, that had not been available to Colonel Milani. As the drone circled more than 6,500 feet above the peak, trees and other objects impeded its view, and it had trouble staying locked on to the men in the fight. 
 
 The imagery technology, still being refined in an Air Force lab, enabled the service to assign each person in the blurry videos a “pixel signature” based on his size, his clothing and the weapons he carried, people who have been briefed said. By identifying Sergeant Chapman shortly after he stepped out of the helicopter with the SEALs, the briefing slides say, its imagery analysts could follow him around the mountaintop, picking him up even when trees or other obstacles partly obscured him. 
 
 Outside experts familiar with the technology said having video footage from the gunship as well as from the Predator drone would have provided the analysts with more tracking angles and clarity. 
 
 “That’s two different eyes, and they could fuse that together,” said David J. Kriegman, a computer science professor at the University of California, San Diego, who has done research in this area. 
 
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 Based on the analysis, the Air Force believes that Sergeant Chapman was unconscious when Chief Slabinski thought he was dead. The sergeant regained consciousness and began engaging enemy fighters in three directions, the slides suggest. 
 
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 The analysis suggests that Sergeant Chapman crawled into the bunker within 13 minutes of the SEALs’ departure, or at about 5:25 a.m. Then, at 6:00, shortly after a rocket-propelled grenade was fired at the bunker, he fatally shot a fighter rushing toward him, according to the briefing. 
 
 A few minutes later, another militant crawled to the bunker’s edge, where, at 6:11, the airman killed him in hand-to-hand combat. 
 
 As a Chinook helicopter carrying Ranger reinforcements approached, the Air Force contends, the sergeant rose up in the bunker for a better angle to provide covering fire. He faced machine-gun fire as he tried to relieve the pressure on the Rangers, whose helicopter was struck by a rocket-propelled grenade. 
 
 It was only then, with rescue tantalizingly close, that two machine-gun bullets struck the right side of his chest, killing him almost instantly. The Air Force says his death was not captured on video. 
 
 Presented with the Air Force analysis, Colonel Milani submitted an addendum to his paper. “With some of the original uncertainty removed, I can state that the probability now lies more in favor of Chapman surviving the original assault,” he wrote. 
 
 The Air Force’s case includes a new analysis of Sergeant Chapman’s autopsy that found that bruising on his forehead could have happened only if he had been alive, making the hypothesis that he had been briefly knocked out more plausible. 
 
 His body, which was recovered later that day, had nine bullet wounds, five below his waist and four above. The sequence of the injuries is not known. But the two fatal rounds entered at what would have been an impossible angle had he been killed where the SEALs said he had fallen, according to people familiar with the Air Force briefing. 
 
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 Lingering Questions 
 
 A team led by the Air Force’s 24th Special Operations Wing commander, Col. Matthew Davidson, briefed Chief Slabinski on the findings late last year. “I didn’t see anything new,” the chief said. “It was just presented differently.” 
 
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 Colonel Davidson said the Air Force could see Sergeant Chapman “moving in and around the bunker” where he and Chief Slabinski had killed the two enemy fighters, the chief said. 
 
 But because the bunker was under a tree that largely obscured it, this was not clear to Chief Slabinski watching the video. 
 
 “You’ve got these little flashes,” he said. “Here’s a sliver of the pixel here, and then it kind of goes away, and there’s another sliver of it, and here’s some muzzle flash stuff.” 
 
 Chief Slabinski said Sergeant Chapman’s assault rifle had been equipped with a suppressor to mask its muzzle flash, but the video showed the man in the bunker firing a weapon with an unsuppressed muzzle flash. 
 
 The chief also questioned why the man shooting in the video appeared to fire on full automatic, rather than with the single aimed shots that the sergeant would have been trained to use. 
 
 At times, Chief Slabinski said, he feels as if he had never left Takur Ghar. He still has “visions” in which he sees fighters on the mountain moving in slow motion, and hears the sound of grenades and gunfire. He has trouble sleeping, and says he has received a diagnosis of post-traumatic stress after a dozen years of war. 
 
 What stays with him the most is that morning he led his team into battle to try to save one man, only to be told later that he had left another fighting for his life. 
 
 “Is it within John’s character to go on and do this? Without a question,” the chief said. “If John did this stuff, I want him to get recognized.” ||||| Patrons in bars across the country are raising toasts in the air, hoping the gesture of gratitude would somehow reach the clandestine Navy SEAL team that took down Osama bin Laden. Millions of others are turning to social networks with their thoughts. 
 
 For many of them, it feels frustratingly incomplete to be deprived the chance to see the faces of those they consider heroes for killing the world's most-wanted terrorist. 
 
 Scores of people responded to the question posed by The Associated Press on its Facebook page: "What would you tell the Navy SEAL team that killed Osama bin Laden if you could convey a message?" 
 
 "I don't know what is more impressive _ that you did this with such excellence and secrecy, or that this was just another day at the office," Pamela Jardieu-Aderman responded. "Thank you to all of the SEALS for a lifetime of sharp swords and full hearts... you guys make America extremely proud, even though we never get to tell you to your faces." 
 
 The 40-year-old freelance grant writer and photographer from Utica, N.Y., said in a follow-up e-mail to the AP that she is glad the SEALs' identities are not being revealed to protect them, but she wishes there was some way the nation could show its gratitude on a large-scale. She suggested a tribute in the form of a White House electronic bulletin board for messages, or a national day of volunteerism, or a ceremony for the SEALs. 
 
 Chicago alderman James Balcer, a Marines veteran, said he would like the city to hold a ticker-tape parade for the unit. 
 
 Obama planned to visit New York City's ground zero on Thursday and meet privately with family members of the victims of the Sept. 11, 2001, terrorist attacks at the hands of bin Laden's al-Qaida organization. 
 
 Jardieu-Aderman said she and her husband donated to the Veterans of Foreign Wars in honor of the elite group that raided the compound Sunday in Pakistan. The Virginia-based Navy SEAL Foundation, which helps the families of SEALs, says their donations have surged dramatically since the news of the raid. 
 
 Nick Flener, 26, a veterinarian in Buena Park, Calif., said he was skeptical, and that the government's limited information was only feeding suspicions. 
 
 "First I would like to know their names and find out why such a historic event is shrouded in so much secrecy," Flener told the AP in an e-mail. 
 
 Gauging how much to tell is a challenge as military special operation groups increasingly work side-by-side with the intelligence community, as the SEALs and the CIA did Sunday. Such covert operation groups are being relied upon more to go after terrorists, and any publicized details of their investigations could make their jobs harder, officials say. 
 
 But touting their success also has benefits: A U.S. House committee on Wednesday approved $10.5 billion for Special Operations Command, which oversees the Navy SEALs unit in the bin Laden mission. The amount represents a 7 percent increase from current levels. 
 
 That elite SEAL unit is known as Naval Special Warfare Development Group, or "DEVGRU." It is made up of a few hundred personnel, and revealing their names would make them a target, Navy officials say. The SEALs are now resting at Andrews Air Force Base outside Washington, D.C., and will likely be honored privately. 
 
 In Virginia Beach, Va., where the team is based, the mayor wanted to throw a parade. City spokeswoman Mary Hancock said the Navy told them that it appreciated the offer but the secretive force _ who call themselves "the quiet professionals" _ would rather avoid the attention. 
 
 That's understood by those who live in Virginia Beach, many of whom served in the military or know someone who does. Neighboring Norfolk is home to the world's largest Naval base. 
 
 "These guys are local boys, and I'm sure that they won't ever take credit for it, being the type of people that they are," said Michael Doyle, a 39-year-old former operations specialist aboard the USS Mount Whitney. "But it makes you proud to be an American _ that's for sure." 
 
 ___ 
 
 Associated Press Brock Vergakis contributed to this report from Virginia Beach, Va.
– An incredible tale of bravery may have surfaced thanks to new "pixel signature" technology applied to 14-year-old videos—but it's a complicated revelation. The New York Times reports those videos, shot by overheard aircraft on March 4, 2002, may show Air Force Technical Sergeant John Chapman fighting al-Qaeda militants and killing two while alone on a mountaintop in Afghanistan. What's so shocking about the footage is not just the bravery. It's that Chapman was supposed to be dead. He was originally there with members of SEAL Team 6, providing support as their radioman. In the midst of a fierce and disastrous operation, Senior Chief Petty Officer Britt Slabinski determined the men needed to get off the mountain. Slabinski couldn't verify the wounded Chapman was dead, but he was nearly certain. So a "dead" Chapman was left behind. The Air Force now suspects Chapman was alive for roughly another hour and tried to provide cover for a helicopter carrying Army Ranger reinforcements (three Rangers were among seven Americans to die that day; some say blame rests at the SEALs' feet). The conclusion comes thanks to technology that assigns those on the ground a pixel signature that can be tracked even when ground cover blocks a man from view. The Air Force secretary wants Chapman given the Medal of Honor; SEAL Team 6 has no issue with that, but hasn't taken a stance on whether Chapman was alive. Slabinski is outwardly skeptical, and suggests the Air Force would welcome a Medal of Honor, which it hasn't seen one of its own get since Vietnam. But a fresh look at Chapman's autopsy may provide further proof he was alive. Read the full story at the Times.