Americans clung to the most traditional of Independence Day festivities in their first celebration of the holiday since the country came under attack on Sept. 11.

They gathered Thursday for parades and fireworks with more than the usual patriotism, many of them more conscious than they were a year ago of what they have to celebrate.

"Enjoy the fireworks, remember those that we lost, and look forward to the future, which is why they all gave their lives," said New York Mayor Michael Bloomberg.

The celebrations were especially meaningful to New York, where the annual Macy's fireworks display paid tribute to victims and heroes of Sept. 11.

"It's breathtaking. It's wonderful. It's beautiful, like gold pouring from the sky," Lois Fontana, of Staten Island, said as the last fireworks sputtered out. "Take that and stick it in your hat, Mr. Bin Laden!"

But some events of the day provoked frightening memories of the attacks. At Los Angeles International Airport, thousands were evacuated after an Egyptian gunman opened fire at the ticket counter of Israeli airline El Al. Three people were killed, including the gunman. Authorities said they weren't sure of a motive.

Tragedy also hit suburban Los Angeles, where a small plane crashed into a crowd at a park, killing the pilot, co-pilot and two people on the ground. A dozen people were injured.

In the nation's capital, a 20-minute spectacle over the Washington Monument felt like a national sigh of relief after months of anxiety, with bursts of light forming peace signs and smiley faces.

The crowd around the Lincoln Memorial was considerably thinner than in past years, with long stretches of empty lawn. On one, a K-9 unit police officer whiled away the twilight by tossing a Frisbee to his bomb-sniffing dog.

"The anniversary of America's independence is a day for gratitude and a day of celebration," President Bush told 8,000 people who crowded into a courthouse square in Ripley, W.Va., to hear his address on the nation's 226th birthday.

At Disney World outside Orlando, Fla., 500 immigrants from 89 countries were sworn in as citizens.

"We are one nation, especially under God. And I don't believe 'under God' should be looked at by a judge so callously," immigration Judge Roberto Morena said to applause.

A federal appeals court ruled last month that the pledge's phrase ``one nation under God'' amounted to a government endorsement of religion, violating the separation of church and state.

In Virginia, 82 people became U.S. citizens during the 40th annual Monticello Independence Day Celebration and Naturalization Ceremony.

Living in America with "all kinds of freedoms around you," people sometimes take those freedoms for granted, said Angela's Ashes author Frank McCourt, speaking at the Monticello event.

After the attacks, he said, "we began to think about being American in a way we never had before."

In Des Moines, Iowa, celebrations began Wednesday night with a Yankee Doodle Pops concert at the Capitol honoring heroes of Sept. 11.

"I think we feel kind of secure out here in nowhere, in the Midwest," said Randy Embrey, 39, whose wife, Krista, dyed her blond hair blue and red and painted her fingernails red, white and blue.

On Philadelphia's Independence Mall, the nation's birthplace, the city conducted its annual "ringing'' of the Liberty Bell.

"Those that attacked us, underestimated our resolve,'' Pennsylvania Gov. Mark Schweiker said. "No one will break this mold called America.''

Jeffrey Orth, known to San Francisco commuters as the Flag Man, walked across the Golden Gate Bridge waving an American flag for the last time — to honks and flag-waving from passing cars.

"I think that sense of celebration of the American spirit will continue without my daily reminder,'' Orth said. "Hopefully all of America will reflect for a moment on the freedoms we enjoy and take for granted.''

Elsewhere in the West, concern over devastating wildfires and a persistent drought put a damper on celebrations and forced the cancelation of fireworks displays.

"All it takes is but one spark from any firework, and we could have a repeat of what happened in Colorado or Arizona,'' said Fire Marshal Ted Bolleter of Santa Fe, N.M.