US President Donald Trump celebrated America's 250th Independence Day on Saturday by describing the nation as the "crowning achievement" of human history while also renewing attacks on what he called communist influences in domestic politics.
His address on Washington's National Mall was delayed for several hours after thunderstorms forced the temporary evacuation of thousands of spectators. Once conditions improved, Trump delivered a speech that was largely patriotic in tone, despite earlier promises to hold a major political rally as part of the anniversary celebrations.
"For two and a half centuries, our American republic has stood as the crowning achievement of human history," he told tens of thousands gathered on the National Mall.
The president paid tribute to veterans of the Second World War, the Korean War and the Vietnam War before linking those conflicts to his criticism of communism.
"Our warriors did not fight communism on battlefields across the world, only to have that menace rear its ugly head right back here in America. We're not going to let it happen," he said.
Trump has repeatedly used similar rhetoric ahead of November's US midterm elections following a series of primary victories by progressive Democratic candidates.
"It's like a cancer, you've got to cut it out," he added.
The president also highlighted recent US military operations against Iran and Venezuela, claiming Washington had "wiped out" Tehran's military.
Although the speech lasted about 45 minutes, shorter than many of his public addresses, supporters welcomed the remarks.
"We love Trump, we loved his speech," said Richard Sullivan, who travelled from Virginia with his wife, Nancy.
"He went through our great history and had a word for the veterans that were here. He makes us proud to be American."
A large fireworks display followed the speech, with Trump saying it would be the world's biggest.
The anniversary celebrations took place during an intense heatwave across the eastern United States. Temperatures reached a record 103F (39.4C) in Washington, marking the capital's hottest 4 July on record, while around 160 million Americans were under extreme weather warnings.
Severe weather also disrupted celebrations elsewhere. Fireworks in New York were brought forward, while events in Philadelphia and Boston were temporarily evacuated because of storms.
Earlier in the day, approaching thunderstorms forced authorities to clear the National Mall before Trump's speech. As crowds attempted to leave, some people resisted the evacuation or tried to re-enter the area, with chants of "Trump! Trump!" heard among sections of the crowd.
Trump defended his decision to proceed with the event despite the weather, telling Fox News that if Allied troops could endure difficult conditions on D-Day, he could do the same.
Among those attending was retired civil servant Randy Cole, who said: "Experiencing a little heat is a lot less than what a lot of people sacrifice to give us this freedom in this awesome country."
The celebrations also reflected the political divisions that continue to shape the United States during Trump's second term. Near Capitol Hill, masked demonstrators, including some carrying Confederate flags and others displaying symbols associated with the white supremacist group Patriot Front, gathered while chanting "Reclaim America!"
A recent Quinnipiac University poll underscored the country's divided mood, with 61 per cent of respondents saying the United States was not living up to the ideals set out in the Declaration of Independence.
