Republican presidential candidate Donald Trump. (Mary Schwalm/AP)
Editorial Page Editor

When we lived in Moscow, people used to ask my wife and me, “Who are you by nationality?”

“Americans,” we’d say.

Invariably the response would come: “Yes, but who are you really?”

Russia, you see, is a kind of melting pot, like the United States, but ethnicities don’t melt in quite the same way. People consider each other first as Armenians, or Tatars, or Jews (yes, “Jewish” is deemed a nationality), and only second as Russian citizens.

That is the kind of thinking that Donald Trump, and the Republican presidential candidates who are pathetically jumping on his nativist bandwagon, would bring to this country.

Trump would abolish birthright citizenship: the principle, embedded in the 14th Amendment to the Constitution, that anyone born in the United States is an American, no matter the legal status of his or her parents. Sen. Ted Cruz promptly claimed he’d always opposed birthright citizenship, too, a claim the Houston Chronicle quickly disproved. Bobby Jindal and Ben Carson joined in, as did Scott Walker, though he didn’t seem entirely sure. Jeb Bush stayed admirably aloof from the mob.

Other conservatives pushed back, but often half-heartedly, arguing that the law would be too hard to change, or that it shouldn’t be the focus of anti-immigration sentiment because it isn’t the biggest problem.

But that’s wrong, too. Birthright citizenship isn’t a problem at all. It’s one of the things that makes America great.

For many countries, what is in your blood, or your DNA, defines whether you can belong. I was shocked that people who had been born in Japan, and in some cases whose parents had been born in Japan, were not Japanese citizens, though they knew no other country. The fact that their ancestors had come (or been brought) from Korea disqualified them from automatic citizenship at birth.

Americans, by contrast, are bound together by a civic ideal.

“Birthright citizenship is much more about us, a nation formed and held together by civic values, than it is about immigrants themselves and an incentive or disincentive to come here legally or illegally,” says Doris Meissner, who ran the U.S. immigration agency under President Clinton and is now a senior fellow at the Migration Policy Institute.

“What’s the belief system, the social cohesion that binds us?” she continues. “A commitment to democracy, participation, equal rights, opportunity, due process, government by the people — people have to be full members of the society for that to be real and flourish.”

Of course most Americans take pride in their ethnic heritage, whether Irish, Ghanaian, Korean or, often, some distinct blend. And often they have paid a price for that heritage. Throughout history, Americans have been discriminated against for their Irish, Ghanaian or Korean ancestry; many earlier incarnations of Donald Trump have whipped up and sought to benefit from such hatefulness.

But eventually each prejudice has been worn down, if not erased, by this shared notion of American-ness, the conviction that citizenship trumps tribe, that any infant born here is as entitled — and as likely — to grow up to be president as any other infant.

Abolishing birthright citizenship would vastly expand and extend what Trump claims is the underlying problem: the presence of so many residents without legal right to be here. His proposal to deport the 11 million is, as he himself said a couple of years ago, an unworkable fantasy. That’s why most Americans support providing some path to citizenship.

But even without such a path, the problem would fix itself eventually. The children of the undocumented will be citizens, and they will grow up — as children of immigrants, legal and illegal, generally have — to better their lot, sometimes to prosper, almost always to contribute.

If, on the other hand, American-born children were denied citizenship, the number of people illegally here would swell. By 2050, according to a study a few years ago by the Migration Policy Institute, nearly 5 million people who had been born here would have no legal claim to remain — or, if having even one undocumented parent was deemed disqualifying, as many as 13 million.

“With all the problems illegal immigration presents, at least it’s a one-generation phenomenon. It self-corrects with the next generation born here,” Meissner told me. “A permanent underclass where disadvantage is transferred generationally is a terrible counter-force.”

After all, why do people around the world want to come to the United States ? In large part it’s because this has always been a place that welcomed risk-takers, profited from their gumption and allowed them — and their children — to answer, when asked their nationality: “American. Really.”

I don’t think Americans will allow a demagogue or his mini-me’s to take that away.

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