Donald Trump praised the United States on its 250th birthday Sunday (AEST) as the "crowning achievement" of human history, as one of the world's largest fireworks displays lit up Washington and thousands of Americans saluted their country in nation-wide festivities.In a speech delayed by several hours when storms forced the temporary evacuation of crowds in Washington, the US President claimed in his much-hyped speech that under his presidency the United States was "prouder than ever before"."For two and a half centuries, our American republic has stood as the crowning achievement of human history," Trump told tens of thousands of people on the National Mall."Over 250 years the world has seen great empires, vast kingdoms, mighty nations, and terrible tyrants. They came and they went. But after two and a half centuries, this American republic still stands tall and strong."Donald Trump and first lady Melania Trump at the Salute to America event in Washington DC. Source: AP / Alex BrandonNews that makes senseYour trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.The US leader also used the speech to renew attacks on domestic opponents he branded communists, push new voting restrictions and boast of the recent military campaigns against Iran and Venezuela, claiming that US had "wiped out" Iran's military.The speech was short by Trump's standards, at around 45 minutes long.A 40-minute long fireworks display, which organisers hope will break world records, then lit up the night sky over the National Mall.Along with opposition against the politicisation of US indpendence day from some quarters in a country that has been deeply divided by his second term in office, Trump faced resistance from the elements.An attendee asks questions to police officers as they evacuate attendees due to severe weather during an independence day event. Source: AP / Manuel Balce CenetaAuthorities allowed the crowd to return to an open field near the Washington Monument where Trump was due to speak, after ordering a weather-related evacuation that forced spectators to shelter in nearby museums and government buildings for a few hours.Attendees had to evacuate the Fourth of July celebrations due to the threat of severe weather near the Washington Monument. Source: ABACA / Gripas YuriWhile many streamed toward exits after the evacuation order, chaos broke out as other attendees refused to leave or tried to surge back in, shouting "charge!" and "Trump! Trump!"Visitors had waited for hours to get into the event, contending with stepped-up security and temperatures reaching 39C. The record-breaking heat wave forced the cancellation of several parades and other events in the area.Crowds were eventually allowed back in to the National Mall after being evacuated. Source: AP / Mark SchiefelbeinOther visitors included the white nationalist organisation Patriot Front. The group posted on social media that it had arrived in the capital, and hundreds of people wearing the group's outfits travelled to the city on metro trains serving the District of Columbia region. Local police said they had not received any reports of violence.Members of the Patriot Front, an American white supremacist group, assemble outside Union Station in Washington DC. Source: ABACA / Douliery OlivierPast presidents have generally avoided in-person appearances at 4 July celebrations, but Trump has blurred the line between official commemoration and campaign-style politics.The Trump administration's Freedom 250 group has largely sidelined a nonpartisan body set up in 2016 to handle the 250th anniversary and has fenced off much of the 2.4km National Mall for a "Great American State Fair" featuring attractions such as a Ferris wheel alongside displays by conservative groups and defence contractors.People join together for prayer and song in David's Tent DC at the Great American State Fair on the National Mall in Washington DC. Source: AP / Rod LamkeySeveral Democratic-led states declined to send delegations, and many performers scheduled to appear dropped out, citing concerns about partisanship. Trump opened the event with a rally on 24 June.Trump visited the iconic Mount Rushmore monument in South Dakota on Friday for an address under the stony gaze of his predecessors George Washington, Thomas Jefferson, Abraham Lincoln and Theodore Roosevelt.Trump delivered remarks during an independence day event at Mount Rushmore National Memorial in Keystone, South Dakota. Source: AFP / Mandel NganHe said America's identity was under "renewed attack" from domestic "radicals and extremists," saving particular ire for a "resurgence of the communist menace."It is a theme that the Republican leader has repeatedly hammered home recently, after the anti-establishment left of the Democratic Party won a string of US primary victories.With the Statue of Liberty behind it, Portugal's NRP Sagres sails through New York Harbor as it takes part in the "Sail4th250" Parade of Ships celebrating 250 anniversary of the United States. The parade of ships included historic tall ships representing 40 nations. Source: SIPA USA / Anthony BeharOutside Washington DC, inclement weather along the Eastern seaboard forced New York's fireworks to be moved earlier and led to evacuations at a concert in Philadelphia and a celebration on the Charles River in Boston.A bolt of lighting struck as fireworks were set off of the Brooklyn Bridge. Source: AP / Seth WenigFireworks explode over the New York City skyline. Source: AP / Pamela SmithFor Americans, the 250th anniversary offers a moment for reflection as well as celebration.A Quinnipiac University Poll showed 61 per cent of Americans thought the US was not living up to the ideals stated in the Declaration of Independence — though most Republicans think it does, and most Democrats think it doesn't.— With reporting by Agence France-Presse and Reuters.For the latest from SBS News, download our app and subscribe to our newsletter.