WASHINGTON, Feb 8, 2023 (BSS/AFP) - President Joe Biden touted America's "unbroken" democracy and resurgent economy in an optimistic State of the Union speech Tuesday -- as he sought to persuade skeptical voters that at 80 he still has what it takes to takes to run for reelection.

Biden's address before Congress and tens of millions of television viewers was a chance for the Democrat, who is expected soon to announce a bid for a second term, to pitch his centrist, populist vision of a country healing after Covid and the turmoil of Donald Trump's presidency.

In a raucous prime-time speech that occasionally more resembled the British parliament's Question Time than the staid annual US tradition, Biden eagerly took on jeering Republicans who newly control the House of Representatives.

Referring to the attempt to overturn the 2020 presidential election by Trump -- who is again seeking the White House -- Biden said that the United States had survived "its greatest threat since the Civil War."

"Today, though bruised, our democracy remains unbowed and unbroken," Biden said.

Biden touted unemployment figures which have hit a half-century low and stabilizing inflation as he told Americans that his economic plan aims to rebuild the country's manufacturing base.

"We're better positioned than any country on Earth right now," he said. 

For decades, "manufacturing jobs moved overseas, factories closed down," Biden said.

"Jobs are coming back. Pride is coming back," he said. "This is my view of a blue-collar blueprint to rebuild America."

Among Biden's proposals in the speech was a new "billionaire tax" he said was designed to "reward work, not just wealth." 

And he hit out at big oil companies he accused of making "outrageous" profits.

"I ran for president to fundamentally change things to make sure our economy works for everyone, so we can all feel that pride," Biden said.

- Taking economy 'hostage' -

Amid deep political divisions, Biden warned Republicans in strong terms not to use their newfound power to block an increase in the debt limit -- a usually rubber-stamp procedure which some conservative lawmakers have refused.

"Some of my Republican friends want to take the economy hostage, I get it, unless I agree to their economic plans," Biden said.

"Let's commit here tonight that the full faith and credit of the United States of America will never, ever be questioned."

Biden's administration warns of financial calamity, with major international implications, if Republicans stick to their guns, potentially pushing the United States into default.

"Fighting for the sake of fighting, power for the sake of power, conflict for the sake of conflict, gets us nowhere. And that's always been my vision for the country: to restore the soul of the nation," Biden said.

But Biden also lobbed pointed criticism at Republicans, accusing some of seeking to wind down entitlements for seniors. Faced with Republicans shouting back, Biden deviated from script to acknowledge that a majority of the rival party did not back ending such popular programs.

- 'We can't turn away' -

Guests at the speech included rock megastar and HIV/AIDS campaigner Bono and Ukraine's ambassador, Oksana Markarova. 

In an address light on foreign policy, Biden received a rousing response when he vowed to support Ukraine "as long as it takes" against Russia's invasion.

Biden's most eye-catching guests were Brandon Tsay, the 26-year-old man who disarmed the gunman in a January mass shooting in California, and RowVaughn and Rodney Wells, the parents of Tyre Nichols, a man whose death after a prolonged police beating in Memphis, Tennessee, shocked the nation.

The president urged Congress to move forward on reforms on policing as well as gun violence.

"We need to rise to this moment. We can't turn away," he said.

Delivering the Republican rebuttal to Biden, former Trump White House press secretary Sarah Huckabee Sanders lashed out at the "radical left" and what she said was an attack against the "freedom and peace" of patriotic Americans.

"It's crazy and it's wrong," said Sanders, who has been elected governor of Arkansas since leaving Trump's administration and is a rising star on the right.

Even if Biden has yet to formally announce his 2024 candidacy, the speech -- followed by two very campaign-like trips Wednesday and Thursday to Wisconsin and Florida -- is expected to give him a big push.

But uncertainties, as well as doubts over Biden's ability to serve a second term that would end after his 86th birthday, may be partly to blame for pessimism in a slew of new polls. An ABC News-Washington Post Poll found that 58 percent of Democrats and Democratic-leaning independents said the party should find someone else for 2024.