US President Joe Biden said his 2024 election rival Donald Trump was willing to "sacrifice our democracy" to regain power, as he kickstarted his campaign with a major speech.
"Donald Trump's campaign is obsessed with the past, not the future. He's willing to sacrifice our democracy, put himself in power," Mr Biden said.
"Our campaign is different... Our campaign is about America, it is about you, it's about every age and background that occupy this country. It's about the future."
The 81-year-old said the fight for democracy was a "sacred cause" in his speech, a day before the third anniversary of the Capitol assault by a pro-Trump mob trying to overturn Mr Biden's 2020 election win.
He said that twice-impeached former president Trump had failed to prevent the Capitol mob assault in 2021, and accused the tycoon and his supporters of still willing to use political violence ahead of the 2024 vote.
"Trump and his MAGA supporters not only embrace political violence, but they laugh about it," the US president said.
He added that Mr Trump had been using language reminiscent of Adolf Hitler's Nazi Party.
"He talks about the blood of Americans being poisoned, echoing the same exact language used in Nazi Germany.
"He proudly posted on social media the words that best describe his 2024 campaign. Quote: revenge. Quote: power in. Quote: dictatorship," Mr Biden said.
"There's no confusion about who Trump is, what he intends to do."
Mr Biden chose a symbolic location for the speech near Valley Forge, the historic site where George Washington regrouped American forces during the war of independence nearly 250 years ago.
The address marked an aggressive start to the year as Mr Biden either trails or is neck and neck with Mr Trump - the man he beat in 2020 - in recent polls.
Symbolism
Mr Trump was impeached but acquitted over the 6 January riots. The 77-year-old now faces a criminal trial on charges of trying to subvert the 2020 election.
The US states of Colorado and Maine have barred him from standing in presidential primaries on the grounds that he had engaged in insurrection over the Capitol events.
Mr Trump has challenged both rulings, and tonight the Supreme Court agreed to hear his appeal against the Colorado ruling that would keep him off the ballot in the western state.
The court will hear oral arguments in that case on 8 February.
Trump campaign spokesperson Steven Cheung immediately reacted to the speech, saying that "Biden is the real threat to democracy by weaponising the government to go after his main political opponent and interfering in the 2024 election."
At Valley Forge, where Washington rallied American forces fighting their British colonial rulers during the bitter winter of 1777-1778, Mr Biden attended a wreath laying session and visited a cottage used by America's first president.
Mr Biden's speech was scheduled for Saturday but brought forward by a day because of a looming winter storm.
Poll worries
The president's attack on Mr Trump came after criticism from some Democrats that the Biden campaign had gotten off to a slow start.
Mr Biden lags behind Mr Trump in some polls, and also has the worst approval rating of any modern president at this stage in his term of office.
The president has failed to convince voters the economy is improving.
Despite further US job growth in December, he acknowledged in a statement that "some prices are still too high for too many Americans."
Migration remains a major headache, while there is division in his party over his support for Israel's war on Hamas, and Congress is blocking his bid for more funds for Ukraine.
Read more:
The Republicans challenging Trump for US presidential nomination
How did the US presidential campaign get to be so long?
Iowa Caucus 2024: How does it work and why is it important?
But perhaps Mr Biden's biggest vulnerability is his age: as America's oldest-ever president, he has suffered a series of trips and verbal slips.
"If the election were held tomorrow, President Biden would lose," William Galston, senior fellow at the Brookings Institution, told AFP.
Yet the Pennsylvania speech showed the Biden campaign was now playing up a straight choice between him and Mr Trump, even though the battle for the Republican nomination does not even start until the Iowa caucuses on 15 January.
Mr Biden's first TV ad of the year warned this week of an "extremist" threat to democracy, featuring images of the Capitol attack set to dramatic music.
