Australia's former ambassador to the United States says Donald Trump's chances of securing the Republican presidential nomination should not be discounted, despite looming legal threats.
Arthur Sinodinos has just finished a three-year posting to Washington, handing over to former prime minister Kevin Rudd.
In an interview with the ABC, Mr Sinodinos said he expected Joe Biden to run for a second term as president on the belief that Mr Trump would be his opponent.
"Never, ever count him [Trump] out," Mr Sinodinos said, regarding the Republican nomination.
"He did have a bit of a low-energy launch to this second campaign of his, but even from the way he can wedge the Republican Party on issues like Medicare and social security, when he gets going, he can be a very effective advocate."
Mr Trump has claimed he could be arrested this week, telling his supporters to "protest, take our nation back!"
Barriers have been set up outside a New York City court amid speculation Mr Trump could be indicted over an alleged hush-money payment to porn star Stormy Daniels during his 2016 campaign.
"Whether he's going to be indicted or not this week, he's very good at dramatising a situation for his own ends," Mr Sinodinos said.
"And so we'll see what particularly happens.
"But it's good to see that some Republicans are pushing back and saying, 'Look, whatever happens, we don't want violence, we don't want blood on the streets as it were, we don't want to repeat, in other words, January 6.'"
Mr Trump is one of only a few declared Republican candidates so far, although Florida Governor Ron DeSantis is widely expected to enter the race.
"I think the challenge for Ron DeSantis is it's one thing to be a governor, it's another thing to go on the national stage," Mr Sinodinos said.
"And on the national stage, sooner or later, you have to take on Donald Trump and he has to show whether he's got the political nous, the rhetorical skills to carry that off.
"If he can be a giant-killer like that, that will immensely enhance his prospects of being president."
Australia needs to 'get on with' AUKUS
Mr Sinodinos also defended the AUKUS agreement with the US and the United Kingdom amid criticism from former prime ministers Paul Keating and Malcolm Turnbull.
Mr Sinodinos downplayed concerns over the impact on Australian sovereignty and argued AUKUS was a necessary strategic decision.
"The point I make now is: failure is not an option," he said.
"Yes, we can debate pros and cons but in the end, a decision had to be made by the Australian government.
"And they made that decision, they crossed the Rubicon. Our job now as a nation is to get on with it."
