Amid unprecedented security, Americans marked the first Independence Day holiday since the September 11th suicide hijack attacks, waving flags and marching in parades today as President George W. Bush urged them to go out and celebrate.
Military jets patrolled the skies above several major cities and thousands of police and security officials watched over crowds who turned out to enjoy firework displays, concerts and such traditional events as New York's annual Coney Island hot dog eating contest.
There have been widespread jitters following unspecific official warnings that there could be more terror attacks, but for many Americans a more immediate challenge was how to cope with a heat wave sweeping Washington, New York and other cities.
Mr Bush kicked off his Fourth of July celebrations with a visit to small town America, telling the residents of Ripley West Virginia - population 3,400 - that he is ready to use the nation's "overwhelming power in the defense of freedom" around the world. Mr Bush exhorted Americans to celebrate despite worries about further attacks after September 11th and pledged to wage his war on terrorism relentlessly.
"The anniversary of America's independence is a day for gratitude, and a day for celebration," Mr Bush told the citizens of Ripley.
Speaking of the war on terrorism that the United States declared after September 11th, Mr Bush said: "Once again, history has called America to use our overwhelming power in the defense of freedom. And we'll do just that."
As Mr Bush visited the red, white and blue-festooned hamlet, which boasts an annual July 4th parade of marching bands and baton twirlers, the government is using everything from military jets to surveillance cameras to protect the nation. While US officials say they have no specific, credible information suggesting attacks are planned for July 4th, many Americans are on edge following the September 11th attacks on New York and Washington that killed about 3,000 people.
The White House today said it had heard of no unusual events to spoil the nation's celebrations, which range from picnics and backyard barbecues to parades and fireworks.
The president was later due back in Washington, where huge crowds assembled on the National Mall in front of the Capitol for a spectacular firework display.
Police fenced off the Mall with a huge security cordon, making people pass through checkpoints on their way to the celebrations.
In Boston, a crowd expected to reach half a million gathered along the banks of the Charles River for the city's firework display.
People filed quietly through checkpoints and donned security issued wristbands before staking out territory on the lawn near the stage where a concert was to be held.