US President Joe Biden has charged Donald Trump and his backers with “extremism” that poses a threat to democracy in the United States, urging all Americans to help counter what he portrayed as dark forces within the Republican Party.

In a speech at Philadelphia’s Independence Hall, Biden accused his predecessor Trump and those backing the Make America Great Again (MAGA) agenda as willing to overturn democratic elections, ignore the US Constitution and “take this country backwards” to a time without rights to abortion, privacy, and contraception or same-sex marriage.

“Donald Trump and MAGA Republicans represent an extremism that threatens the very foundations of our republic,” Biden said. “As I stand here tonight, equality and democracy are under assault. We do ourselves no favour to pretend otherwise.”

The hard-hitting speech comes barely two months before the US heads to the polls in bitterly contested midterm elections that Biden has called a crossroads for the nation.

Aides say the president is increasingly concerned about anti-democratic trends in the opposition Republican Party, and its Trump-aligned factions.

Al Jazeera’s White House correspondent Kimberly Halkett said Biden was focusing on an area where the Republicans were seen to be vulnerable, following the violent assault on the Capitol by Trump loyalists in January 2021.

“This is a deliberate strategy on the part of the Democrats,” she said.

Biden, who largely avoided referring to Trump by name during his first year in office, has grown increasingly vocal about his rivals in the last weeks and likened the MAGA “philosophy” to “semi-fascism”.

Aware of the potential risks from such outright attacks, 79-year-old Biden has sought to balance his criticism with an appeal to more traditional Republicans to make their voices heard, but on Thursday Republican leaders accused him of only furthering political divisions.

“Instead of trying to bring our country together to solve these challenges, President Biden has chosen to divide, demean and disparage his fellow Americans,” said House of Representatives Republican leader Kevin McCarthy, referring to issues such as crime and inflation.

‘I will not stand by’

Some historians and legal scholars have cast the political stakes in stark terms, saying free elections and commitment to the rule of law hang in the balance in the midterms.

They say losing Congress would not only make Biden a lame-duck president, but would also allow Trump sympathisers, some of whom never accepted Biden’s 2020 victory and want to overhaul voting systems, control of certifying the results of the next presidential election.

Biden alluded to the concerns, saying “I will not stand by and watch elections in this country be stolen by people who simply refuse to accept that they lost.”

The speech echoed Biden’s signature 2020 campaign promise to restore the “soul of the nation” and, by implication, purge the values associated with Trump. In the nearly two years since Biden was elected, Republican voters have mostly backed candidates aligned with the former president; more than half say they believe Trump rightfully won the election.

Former advisers to Trump and Justice Department officials have testified that there has been no evidence of any widespread fraud or manipulation of voting machines.

Judges, including ones appointed by Trump, dismissed dozens of lawsuits filed after the election, and Trump’s own attorney general called the claims bogus. (Al Jazeera)

•PHOTO: President Joe Biden warned of the threat from 'extremism' in a speech in Philadelphia, Pennsylvania, on Thursday [Matt Slocum/AP Photo]

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