Six months after the attack on Pearl Harbor, a weakened and outnumbered U.S. fleet limped north to confront a flotilla of Japanese ships advancing on the remote Pacific atoll of Midway.

A U.S. defeat would have enhanced Japan's naval superiority in the Pacific. Instead, the U.S. sank four Japanese aircraft carriers and snatched the military advantage from Tokyo.

Next week marks the 65th anniversary of the three-day battle that changed the course of World War II. Three Midway veterans in their 80s and 90s and the current Pacific Fleet commander will visit the island 1,300 miles northwest of Honolulu tomorrow for a ceremony hosted by the U.S. Fish and Wildlife Service, which today runs a nature reserve on the atoll.

"Americans like underdogs, and here we are underdogs," said Donald Goldstein, a University of Pittsburgh history professor. "I think that's what made it so good — that we shouldn't have won and we did."

The victory came after a string of U.S. setbacks in the Pacific.

Japanese forces ousted the U.S. from Wake Island, Guam and the Philippines in rapid succession in the months after Pearl Harbor. Japan also drove the British, U.S. allies, from Singapore.

By targeting Midway, the Japanese navy aimed to take control of the U.S. patrol plane base there and destroy what was left of the U.S. Pacific Fleet. Conquering the island was a way to protect the Japanese homeland from U.S. air raids and prevent the U.S. from interfering with Tokyo's plans to dominate the Asia-Pacific.

The U.S. thwarted Japan's intentions with a mixture of codebreaking, smart decisions and luck.

The Navy's intelligence experts deciphered encrypted Japanese communications, giving Adm. Chester Nimitz, the U.S. Pacific Fleet commander, the precise time of the planned assault and what route Japan's ships would travel to Midway. He was also given notice of what vessels Japan would bring to the battle.

Both nations lost dozens of fighter jets, dive bombers and torpedo planes as they each sought to sink the other's aircraft carriers.

But the Americans had the benefit of knowing roughly where at sea their Japanese opponents were and how many ships their enemies had. Japan's commanders were forced to guess about their foes.

The U.S. lost one carrier, 145 planes and 307 men.

Japan lost four aircraft carriers, a heavy cruiser, three destroyers, 291 planes and 4,800 men. The defeat was so overwhelming that the Japanese navy kept the details a closely guarded secret, preventing the story of the battle from coming to light in Japan until after the war.

Goldstein, the co-author of "Miracle at Midway," said Japan's military never recovered from the loss because its industrial sector was unable to manufacture replacement aircraft carriers quickly enough to retake the advantage.

Over the next three years, U.S. forces moved increasingly westward after hard-fought battles to deny Japan access to Guadalcanal and to retake Guam. The island-hopping led the U.S. to Iwo Jima and Okinawa before Japan surrendered after the atomic bombings of Hiroshima and Nagasaki in 1945.

"Midway made it possible for us to take the offense. Before that it had been all defense," Goldstein said.

The Navy handed the two islets that make up Midway — Sand and Eastern islands — over to the Fish and Wildlife Service in 1996. The agency has held commemorative ceremonies every year since, though the last major observation was for the 60th anniversary in 2002.

Midway enjoys quieter days today. Its primary residents are the hundreds of thousands of Laysan albatross, or "gooney birds" that have long nested there. Only a few dozen humans live on site to run the wildlife refuge.

The atoll is on the upper northwest end of the national marine monument President Bush created last June around the Northwestern Hawaiian Islands.

The nature reserve, known as the Papahanaumokuakea Marine National Monument, is home to endangered species like the Hawaiian monk seal and is the largest marine conservation area in the world.