President George W. Bush praised the veterans of World War II, whose numbers include his own father, former President George H.W. Bush, also in attendance.
"When it mattered most, an entire generation of Americans showed the finest qualities of America and humanity," the younger Bush said.
Today's dedication ceremony had its roots in 1987, when legislation was introduced to create the $175 million memorial, the Washington Post reported.
"It has taken too long to erect this monument," said NBC anchorman Tom Brokaw, whose best-selling book about the war, "The Greatest Generation," was cited throughout the day.
The event was described as the country's largest organized gathering of surviving veterans in 60 years.
Security was extraordinarily tight.
Although 75 percent of all World War II veterans have died - about 1,000 World War II veterans die each day -- as many as 100,000 were expected to be on the Mall for Saturday's ceremonies.
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