Harvard medical researcher Soumya Raychaudhuri, of Brookline, pauses during an interview at Brigham and Women's Hospital in Boston on Tuesday, Jan. 31, 2017. Raychaudhuri awaits the fate of a new hire, Samira Asgari, an Iranian national who was not allowed to board a flight in Switzerland to Boston due to the travel ban issued by President Donald Trump. 
Harvard medical researcher Soumya Raychaudhuri, of Brookline, pauses during an interview at Brigham and Women's Hospital in Boston on Tuesday, Jan. 31, 2017. Raychaudhuri awaits the fate of a new hire, Samira Asgari, an Iranian national who was not allowed to board a flight in Switzerland to Boston due to the travel ban issued by President Donald Trump.  Credit: AP PHOTO

I am the son of a refugee. I owe my very existence to the nations that took my father in when he was forced to flee his native land almost 100 years ago.

So I took it personally when President Trump issued an executive order Jan. 27 barring refugees and citizens from seven majority-Muslim countries from entering the U.S. He has disrupted the lives of many good people, he has sparked more protests against his impulsive decisions, and he has angered European leaders – and many Republicans, too.

My father was 15 when the Russian Revolution occurred in the middle of a world war. He and his family had to flee from their home in Saint Petersburg. First they went south to Crimea, then to Kiev and Warsaw, behind enemy lines, before winding up in Riga, a port city in Latvia.

By this time the war was over, and the Red Army was closing in on Riga. My father and his family would have been at risk of execution if they had stayed. Two of my father’s uncles who remained in St. Petersburg were killed.

They were saved by a British ship that picked up 300 refugees before leaving Riga. My father and his family went to Denmark because that’s where the ship was going. By the time they set foot in Denmark, the Red Army had arrived in Riga.

Seventy years later, in the 1990s, Denmark took in a lot of refugees. A study found that, as a result, more Danes moved into skilled jobs and away from manual labor. The immigrants contributed more to their new home than they took from it, bringing new skills, taking jobs that had been hard to fill, and starting new businesses, the study found.

The U.S. used to welcome immigrants, and many of them made major contributions to our country. I’m thinking of physicist Albert Einstein, writers Elie Wiesel and Vladimir Nabokov, Google co-founder Sergey Brin and many others.

I’m also thinking about Samira Asgari, the 30-year-old Iranian citizen who was scheduled to fly to Boston Saturday to start a postdoctoral fellowship at Harvard Medical School. She was stopped in Frankfurt and told she couldn’t board the plane to the U.S.

My father spent a few years in Denmark before concluding that he couldn’t return to Russia anytime soon. So he came to the U.S. at age 23. He had no job prospects or friends and spoke little English. He boarded a train to Colorado, where he worked as a miner and a waiter, then went to San Francisco, where he worked as a pall bearer. In Los Angeles he worked, occasionally, as a movie extra, and sometimes didn’t know where his next meal was coming from.

Although he never finished high school, he wrote six books and worked for the State Department in Washington, D.C. He raised a family and paid his taxes. If a Trumpian president had been in office in 1925, he might have been sent back to Russia because there was no assurance that he was not a Communist.

There have been more than five million refugees from the Syrian civil war, and the migrant and refugee problem is likely to get worse because of climate change. In Syria, the civil war was preceded by the worst four-year drought in its history, forcing farmers and herders to move to cities. Food scarcity, water insecurity and extreme weather contributed to the refugee crisis.

It was a cruel irony that Trump issued his executive order on International Holocaust Remembrance Day. It seems that he wants to move the country away from respecting all religions to one that favors Christians. Many Christians are stepping up now and denouncing this violation of the First Amendment.

Trump acts as if he was elected dictator, not an insurgent who got a minority of the votes. He says he’s changing our immigration policy to protect our security, while ignoring that most murderers in this country are American men with guns.

Samira Asgari is not a threat to our national security. But Donald Trump is, by provoking terrorists who can now claim that they’ve been right all along in saying that Americans hate Islam.

My father endured a lot of hardships when he came to this country, and I expect that will be the case for many refugees today. It isn’t easy to learn a new language, adjust to a new culture, and to move on with your life after you’ve lost everything. But he adapted and ultimately thrived, and I think many of today’s refugees can too, if given the chance.

Nick Grabbe, of Amherst, a former editor and writer at the Gazette, is a member of the Amherst Charter Commission.