As respectable Republicans panic over Donald Trump’s storm of insults against Hispanics, Democrats may be tempted to sit back and watch the other party estrange millions of potential voters. But they do so at their own peril.

Democrats already have the luxury of being far less offensive, whatever position they take on immigration. But they must take a position, and that position must draw a line between legal and illegal. To do so, they can’t flinch when advocates of open borders unleash unpleasant accusations against any Democrat who attempts to honor that line.

Fear of uncontrolled immigration is not limited to crazed right-wing white folk. Blacks have long felt themselves unfairly replaced by immigrants. As poet Toni Morrison wrote, “whatever the ethnicity or nationality of the immigrant, his nemesis is understood to be African American.” The evidence remains anecdotal, but many blacks have expressed support for Trump over this issue.

Many immigrants also have highly mixed feelings about open borders. To my surprise, a nonwhite nurse from the Philippines, a friend, has been sending me pro-Trump literature.

Over half of Latinos in the U.S. workforce were born in this country. They are thoroughly American. And that doesn’t count the huge number of foreign-born Hispanic workers here legally.

Their wages and benefits are also being depressed by unauthorized migrants willing to work for less. And as many states and cities raise their minimum wages, some employers will be even more tempted to hire the undocumented under the table and at lower pay.

Many Democrats who honor and admire immigrants remain frustrated by a surge of unskilled foreign workers into the hard-hit bottom rungs of the labor market. It is one cause of economic inequality. A Pew Research Center poll has 79 percent of Democrats saying that the immigration system needs to be completely rebuilt. And just look at the exasperated comments by self-described liberals following opinion pieces praising the benefits of immigration without making any distinction between legal and not.

The reasonable path out of the mess is to legalize most of the undocumented while stopping future unauthorized migrants. President Obama valiantly tried to win over skeptics by demonstrating a will to enforce. For these efforts, the open-border crowd on the left condemns him as “deporter in chief.”

Note the hostile reaction to Obama’s recent move to discourage a new surge of illegal immigration from Central America. Agents for his Department of Homeland Security had arrested for deportation 121 migrants whose claims for asylum were denied in the courts.

“Our borders are not open to illegal migration,” Homeland Security Secretary Jeh Johnson said. In any other country, that would have been an unremarkable statement.

But advocates for undocumented immigrants and some Democrats in Congress went ballistic. They accused Obama of crimes against innocent families.

If powerful Democrats can’t back deporting 121 people whose appeals for asylum were turned down, why would the American public trust them to respect a comprehensive immigration solution?

As the party of unions and working people, the Democratic Party used to be more hawkish on immigration than the GOP — and with the support of its immigrant members. At a certain point, though, many leading Democrats replaced the labor agenda with an ethnic one.

Because Trump’s magic sauce includes a strong defense of the social security net, Bernie Sanders thinks he could attract some of the populist’s working-class supporters. He or Hillary Clinton probably could. But each must first make clear that our national labor market can’t be a global one. That means defending the principle, without apology, that who and how many come into this country matters.

Froma Harrop is a syndicated columnist. Follow her on Twitter @FromaHarrop. She can be reached at fharrop@gmail.com.