Joe Biden excoriates Donald Trump, calling him threat to US values, institutions

US President Joe Biden launched a fresh salvo on his principal Republican rival of Oval Office Donald Trump Thursday terming him an "extremist" who is posing a grave threat to the democratic values and institutions of the US, calling upon supporters to rise up against the menace. 

Joe Biden regarded Donald Trump as driven by "vengeance and vindictiveness", calling his hard-right Republican friends posing a threat to the freedom of speech and the supremacy of the law.

In his Arizona speech, the 80-year-old Biden avoided commenting on the former president's criminal indictments including Trump's role in subverting 2020 election results that caused a brutal riot which attacked the US Capitol on January 6, 2021.

However, the Democrat did not hold back in the speech about what he said the country would risk from a second Trump term.

"We should all remember: democracies don't have to die the end of a rifle," the commander-in-chief said adding that "they can die when people are silent when they fail to stand up or condemn threats to democracy."

2024 presidential hopeful said there was "something dangerous happening in America" and that the Republican party was "driven and intimidated" by Trump's MAGA (Make America Great Again) fringe.

"They're not hiding their attacks. They're openly promoting them, attacking the free press as the enemy of the people, attacking the rule of law, fulminating voter suppression."

Biden criticised Republicans in particular for failing to speak up after Donald Trump recently accused a top US military officer of treason, and lashed out at hardline Trump-allied Republicans for pushing America towards a government shutdown this week.

But Biden reserved some of his toughest words for Trump himself, unusually addressing him by name instead of referring to the Republican as he usually does as his "predecessor" or "the last guy".

Joe Biden unviels Donald Trump's motivation

"Trump says the constitution gave him 'the right to do what he wants'," said Biden, referring to statements made by indictment-stricken Trump about how he saw his powers in office.

"I've never even heard a president say that in jest — not guided by the constitution or by common service and decency towards our fellow Americans, but by vengeance and vindictiveness."

At one point, after being interrupted by a climate change heckler, Biden said to the audience: "Democracy is never easy — as was just demonstrated."

The speech came as House Republicans on Thursday launched impeachment inquiry hearings into Biden, based on unproven allegations that he lied about his son Hunter's business dealings.

Biden, however, touted his bipartisan credentials by using the speech to hail the legacy of his frequent political opponent and close friend — the late Arizona senator John McCain.

McCain, a Vietnam war hero, was defeated in the 2008 presidential election by Barack Obama, with Biden on the winning ticket as vice president. But the two men put aside their differences particularly after Trump won his own presidential election in 2016.

Biden described McCain, who died in 2018, as a "proud Republican who put country first."

McCain loathed Trump, withdrawing his support for him in the 2016 presidential election and saying before his death from brain cancer that he didn´t want him at his funeral.

The feeling was mutual, with Trump mocking his war hero status in 2015.

Biden, by contrast, delivered a eulogy at McCain's funeral, saying that he "loved" him and that their friendship transcended political differences.

While the US election is still more than a year away, Biden and Trump notched up their first major head-to-head skirmish this week with duelling visits to auto industry workers in Michigan, another battleground state.

Biden's speech also comes the day after seven other Republican presidential hopefuls held a campaign debate in California. Trump, who holds overwhelming leads over all of his rivals, snubbed the event.