I’ve seen what harsh immigration policies did to Australia. Americans may not be fully prepared for what Donald Trump has in mind.

Many Australians follow American politics and trends. We have a lot in common and are allies. We also relish our rivalry (witness this year’s Olympic swimming events).

Like you, we experienced a spike in cost-of-living pressure, interest rates, and inflation, driven by supply-chain disruption from COVID-19 and war. And the governments of all advanced economies face the same grievances — including concerns about immigrants and the other recent arrivals on our shores.

As someone who has seen what draconian immigration policies can do to the social and cultural fabric of a nation, I urge all Americans to ask themselves: What will you do when Donald Trump starts to implement the mandate you gave him?

When it comes to the appalling treatment of asylum-seekers and refugees, Australia wrote the playbook. We’ve been detaining refugees and “stopping the boats” — mostly from Indonesia — since before 9/11.

We’ve been unconstitutionally locking up asylum-seekers since the 1990s, most recently in detention centers on remote, non-Australian islands, through deals with Nauru and Papua New Guinea. Fine form for a nation that began as a penal colony.

Educated Australians are ashamed of our “stop the boats” politics. This has been on top of the decades of forcibly separating Indigenous children from their parents. These moral failings leave the deepest of stains and take generations to heal.

We have a long history of demonizing refugees and immigrants, of punishing innocent people. Yet, modern Australia is a nation of migrants. America’s story is not much different. Our nation is vastly richer because of our multicultural complexion, as is yours, and old white men like me need to learn to appreciate it.

Adolphus Busch, the cofounder of Anheuser-Busch, was a German migrant, and Albert Einstein, who gave America its atomic might, was a refugee fleeing Nazi Germany. They added to the “greatness” of America. So while there is a slim chance a migrant will eat your dog, it is more likely you’ll find them to be the next Busch or Einstein.

Finally, Trump has been called a fascist. Certainly, he seems to be an authoritarian, and I wonder what you will do when they start to round the “illegal” immigrants up. Possibly people you know.

I can assure you, from decades of demonizing migrants and asylum-seekers by right-wing politicians, radio shock jocks, even progressive politicians seeking to neutralize the issue, the asylum-seekers are not at fault and are not the problem. Yes, have better border control, but don’t make these people the scapegoat for your social and economic ills.

The Germans went along with Adolf Hitler’s plans to round up the Jews because the Nazis managed to persuade ordinary people to adopt a set of lower social values. Is Trump doing the same?

When Trump appeared as a presidential contender in 2016, most Australians thought he was a joke. Give us Ronald Reagan, Arnold Schwarzenegger, or Clint Eastwood any day, but surely not Trump.

I later understood that the “anyone but a Clinton” sentiment was so strong that a complete outsider made sense. But still, Trump?

For us, Trump remained a joke throughout his presidency: covfefe in 2017, his bromance with Kim Jong Un, and injecting bleach as a COVID cure — at least until too many Americans died, then it wasn’t funny anymore.

The most powerful country on Earth was entirely incompetent in the face of COVID with Trump at the helm.

In March 2023, the mortality rate from COVID in the U.S. was around 341 deaths per 100,000 patients. In Australia, it was nearly 77, the United Kingdom approximately 325, and Canada just over 135, according to Johns Hopkins University and Medical. No other developed economy came close to the death rate in America except the U.K., with its own version of Trump in Boris Johnson.

Trump politicized a public health crisis, playing a deadly game for years. We were astonished. How could a protective face mask become a symbol of political allegiance? Live free or die, all right.

Trump’s mismanagement of the COVID crisis saw him tossed out in 2020, unfit for another term, as were many politicians, including our prime minister, Scott Morrison, in 2022, who was a COVID master compared with Trump.

Still, as recently as the beginning of this year, 36% of adult Americans thought the 2020 election was illegitimate.

It would take a lot more than a politician being tossed out for mishandling a pandemic for Australians to believe there was something wrong with their electoral system, and we are still voting with pencil and paper.

Was the 2016 election stolen? Was the 2024 election stolen? No, just 2020? Sorry, folks, but you can’t have it both ways.

No Republican is asking for a 2024 recount, despite Trump’s suggestions it too would be rigged. Give us a break. Those who went along with the election lie should now publicly confess their sin.

Your very own Stanley Milgram conducted experiments to see how readily Americans would obey orders and accept immoral standards, in the same way the Germans did under Hitler’s authoritarian rule. Milgram proved unequivocally that most would.

Will you?

Michael Parker is a public communication consultant and teaches in the school of communication at a leading university in Sydney.