‘I have seen this before. We will not go silently.’

My family and I have survived two revolutions: Russia, 1917 and Iran, 1979; my grandparents escaped the communists and I, the Islamists. From 1982 to 1984, when I was in my teens, I was a prisoner of conscience—charged with anti-revolutionary activism, in Tehran’s notorious Evin prison. While there, I was beaten to a pulp, tortured, and raped. I can smell propaganda miles away, and it makes me want to vomit.

I am smelling it now. Wisdom, which is necessary for the discovery of truth, needs experience, knowledge, pause, logic, and critical thinking, all of which require time. Trump’s America is showing itself to have no respect for measured process or human dignity. Truth and justice have become its roadkill.

It took me years to deal with post-traumatic stress disorder and bear witness against the crimes of the Iranian regime. My first memoir, Prisoner of Tehran, was published in 2007. Since then, during the academic year, I have been giving an average of three talks a week at conferences, high schools, and universities, travelling from my adopted home in Canada to various countries. To me, bearing witness cannot be a part-time job; it asks for my every breath. I have testified at the UN Human Rights Council in Geneva while the Iranian authorities sat only metres away from me. They avoided eye contact, but I stared at them while I recounted the details of the suffering they had inflicted on me.

On Jan. 28, 2017, only because I was born in Iran, Mr. Trump decreed that I and other Canadian dual citizens like me would not be allowed into the United States, where I have given many talks in recent years, the last one only a few weeks ago in Washington, D.C. Since the initial news, Canadian officials have attempted to clarify the position, and it could be that I am now not banned. Am I safe to try? I have spoken at Tufts University, Yale, and Berkeley. Yet, Iranian officials, sponsors of terror against their own people and worldwide, who have directly or indirectly had a hand in my torture and the murder of my friends, are allowed to go to the U.S. with diplomatic passports. Mr. Trump claims that he’s protecting the people of the U.S., but he can’t even get that part right, according to his own twisted logic. Countries like Saudi Arabia, Pakistan, and Afghanistan—whose citizens have led most terror attacks on U.S. soil—are not on his list of dangerous countries, whose citizens are banned from entering the United States.

I work with refugees in Canada. The vast majority of Syrian refugees are Muslim; most of them have lost everything, including loved ones. Most are good, very good people. As a Christian, I humbly believe it is my duty to help the most vulnerable, regardless of their religion, colour of skin, sex, sexual orientation, race, etc.

It seems Mr. Trump is a different kind of Christian. A master of propaganda, he makes me think of Joseph Goebbels, the minister of propaganda of Nazi Germany who famously said: “It would not be impossible to prove with sufficient repetition and a psychological understanding of the people concerned that a square is in fact a circle. They are mere words, and words can be moulded until they clothe ideas and disguise.”

There will be those who say I have no right to compare Mr. Trump to the leaders of the Soviet Union, the Islamic Republic of Iran, Nazis or fascists, the likes of whom now call themselves “alt-right.” But I invite them to read some history, pause, and think. People are people. Everywhere. At any point in time. From any ideology, religion or skin colour. No one is immune to hatred and evil. The Nazis were not from another planet. They took the justified grievances of the citizens of Germany after the First World War, and they manipulated the negative emotions of the poor and the wronged of their society in a country that had a democratic process in place. The people of Germany were as good as any other who fall prey to propaganda. It’s easier than you might think. In Iran, I saw average people do terrible things in the name of national security, self-defence, and God, among other things. Being white and Christian doesn’t automatically make us good persons.

Squares have become circles yet again in a world of “alternative facts,” where—of course not for the first time—politicians claim that being popular and attracting crowds is a sign of righteousness. Have they forgotten the stadiums and streets that Hitler filled, and the millions who rallied, for example, in support of the 1917 Russian and the 1979 Iranian revolutions? Both movements promised freedom and democracy and made grand claims, but they did not deliver; they created two of the worst dictatorships the world has ever seen. They both divided the world into “us” and “them,” as did the Nazis. They designated certain “others” as enemies that “we” needed to unite against them for survival. For the Nazis, it was the Jews, for the Bolsheviks the rich, for Ayatollah Khomeini and his followers in Iran the Americans and Western values, and now for Mr. Trump and his supporters it is legal and illegal aliens, especially Mexicans and Muslims, in addition to most of the rest of the world.

We have lost track of what truly matters. In the age of information, we’re drowning in words that claim to be the “truth.” But information doesn’t necessarily translate into wisdom. “Reality” TV and propaganda’s unholy union has given birth to “alternate facts,” a term which means lies, just as “enhanced interrogation techniques” means torture. President Trump barges from one ill-thought decree to another, leaving a trail of destruction and pain behind.

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Fear is the strongest human emotion. It usually leads to anger and hatred and eventually violence, which are difficult to diffuse but can be manipulated, shaped, and used with propaganda—a bloodthirsty process that we have seen many times. What Mr. Trump is doing is nothing new. “Never again” is dying a painful death, a faucet dripping in the background or ordinary life, leading us to a dangerous place that those who truly know history understand well, a place that makes me shudder.

Those who try to justify cruelty, lack of compassion, disregard for human dignity, lies, torture, theft, fraud, murder, and other evil acts in the name of this or that are up to no good. Period. Do not believe them. Wrong is wrong. A circle is not a square; this has nothing to do with one’s opinion. We should not allow lies to masquerade as the truth, or injustice as justice.

Canada took me in when the country of my birth, Iran, spat me out. It gave me a safe place and the time to deal with the past. It gave me my voice back and the strength to stand up to all forms of injustice again. My Canadian passport is my most valued possession. I have never been back to Iran since I left it in 1990 and I will not return, because if I do, I will be arrested, tortured, and executed for my continuing outspokenness. Canada, I hope to have made you proud. Prime Minister Trudeau has been a beacon of hope. Thank you. On Saturday, when those like me who happen to have dual nationality felt like the ground disappeared from under our feet, he stood up for us. Thank you, Mr. Prime Minister.

No, Mr. Trump. We will not go silently into the dark, ugly night you are creating. You can claim whatever you will, but your actions speak loudly; they remind me of the insane fatwas of the Islamist fundamentalists who I was lucky enough to escape.

Marina Nemat is the author of Prisoner of Tehran and After Tehran, chair of PEN Canada’s Writers in Exile Committee and co-chair of the Board of Directors, Canadian Centre for Victims of Torture.