Australians shun Trump but back alliance as China looms

While Australians by in large don't care for Donald Trump, their fear of China is trumping negative views of the US alliance.

Half of Australians think a second Trump presidency would be bad for their nation, but only a quarter would want to withdraw from the US alliance if he's elected, according to a United States Studies Centre report.

This is compared to 37 per cent supporting a withdrawal in the same circumstance the year before.

"Perceptions of Trump haven't changed but perceptions of the US alliance have," report author Jared Mondschein told AAP.

An increase in support for the alliance under Mr Trump (50 per cent of Australians) came despite the majority of respondents in all three nations expressing concern about the outbreak of a conflict and political division under his presidency.

Australian, Japanese and American views about the threat China poses are more closely aligned than in previous years, the data shows.

"They collectively see China as a challenge," he said.

The centre's CEO Mike Green says the increase in support in the alliance parallels what is happening in Japan, South Korea and the Philippines - other US treaty allies.

"This is a common theme amongst US allies and the obvious explanation is the China factor," he told AAP.

Challenges to national security worldwide including Russia's invasion of Ukraine, North Korean belligerence and conflict in the Middle East reinforced the need for powerful allies, Mr Green said.

"Even with Trump in charge, there isn't a lot of options," he said.

Toned down rhetoric from the former president towards Australia compared to 2016 has also affected the view that the US alliance can survive successive presidents, Mr Green said.

On Australia's plan to acquire nuclear-powered submarines, half of Australians supported it while one in five disagreed.

But half also thought the AUKUS alliance under which Australia would get the submarines from America locked it into supporting Washington in a war.