The former US president survived the shooting, with a bullet clipping his ear at a political rally, while an audience member was shot and killed.
What happened in the United States was "shocking and distressing" and shouldn't be repeated in Australia, Victorian federal Liberal MP Aaron Violi said.
"It's vital as leaders in Australia we don't let these challengers infiltrate Australian politics," he told AAP.
The pressurised political environment in the US and history of violence - including at the January 6 riots - meant while an assassination attempt wasn't inevitable, "it was pretty good odds", extremism researcher Kaz Ross said.
"The political tempo in America is at fever pitch," Dr Ross told ABC radio.
Young men in particular "could get very agitated and take some rash, violent steps to resolve political problems", she said.
Dr Ross also warned about a "culture war" and divide that stemmed from political debate being imported from the US.
Conspiracy theories were abundant online and while the motive of the alleged shooter was yet to be determined, "whatever his motives were, people will play it up to suit their side of politics," Dr Ross warned.
"Basically it's just choose your poison," she said of the varying conspiracy theories.
Australians were concerned about "how ugly and divisive" politics was becoming, Treasurer Jim Chalmers said as he warned against violence and extremism being normalised.
Democracy was supposed to help people bridge gaps and differences, "not magnify and horrify them", Dr Chalmers said.
The assassination attempt provided an opportunity for democratic societies around the world to denounce extremism and violence, he added in a call for unity.
"We should be able to settle our differences with votes, not violence," he said.
Opposition home affairs spokesman James Paterson expressed concerns about people using violence to make political points, saying democracy could erode very quickly.
It was important people responded in "a calm and measured way to ensure there's no further escalation of violence".
Despite having stronger gun laws, Australians couldn't be complacent against violence, Senator Paterson said, pointing to two UK parliamentarians who were murdered in the past decade despite similarly tough firearm restrictions.
"There are some troubling signs that there are trends towards using violent means in Australia to try and intimidate parliamentarians and their staff," he told ABC radio.
"We cannot allow that to take hold here."
