Trump visits Kenosha, not to urge racial healing but to back police

US President Donald Trump defied requests to stay away and visited Kenosha, Wisconsin, not to urge racial healing but to express support for law enforcement in a city rocked by civil unrest.

With the United States polarised over issues of racial injustice and police use of force, Trump is appealing to his base of white supporters with a "law and order" message as opinion polls show him cutting into the lead of his Democratic rival, former vice president Joe Biden.

Meanwhile, Trump has largely overlooked the racial wounds caused by police use of force and played down the more than 180,000 US deaths from the coronavirus pandemic.

The Republican president also threatened to send more federal officers into cities governed by Democratic mayors even if local officials objected, saying, "At some point ... we'll just have to do it ourselves."

Trump did not visit Jacob Blake, who was paralyzed from the waist down after a white police officer fired at his back seven times on August 23. He did not meet Blake's family either, but did meet with his mother's pastors.

He promised instead to rebuild Kenosha and provide more federal spending to Wisconsin, a political battleground state that Trump won narrowly in 2016 and badly needs to keep in his column as he seeks re-election on November 3.

His election opponent, Biden, has accused Trump of stoking violence with his rhetoric. Biden's campaign on Tuesday seized on Trump's trip to Kenosha as it accused his administration of seeing "violence as a winning electoral strategy".

The president visited a burned-out furniture store that was destroyed in the upheaval and then a makeshift command center to praise National Guard troops who were called in to reinforce local police after several nights of peaceful protests gave way to looting, arson and gunfire.

"These are not acts of peaceful protest, but really domestic terror," Trump told local business leaders in a high school gym.

Peaceful demonstrators have complained that violent agitators, often white, have hijacked their protests with property damage. But many have also sharply criticized the police, saying the United States needs to completely rethink its law enforcement practices.

"To stop the political violence, we must also confront the radical ideology. ... We have to condemn the dangerous anti-police rhetoric," Trump said, adding that without his help Kenosha would have "burned to the ground."