Presumptive Republican nominee Donald Trump speaks in Dallas on June 16. (Ron Jenkins/Getty Images)

WHEN DONALD Trump launches attack after attack on American Muslims, we’re confident he doesn’t speak for most of his countrymen. But there’s reason to worry that, whether Mr. Trump wins or loses, his poison will spread. A couple of recent surveys suggest that innocent Americans, including children, may be paying a price for his bigotry.

Mr. Trump’s outrageous claim Monday that American Muslims are complicit in lone-wolf terrorist attacks can only heighten fears among Muslim students in the D.C. area who, The Post’s Donna St. George reported this week, experience high rates of harassment because of their religion. Studies from the Muslim Community Center (MCC) in Silver Spring and the International Cultural Center (ICC) in Montgomery Village show nearly one-third of Muslim students have suffered verbal or physical abuse based on their faith. In the wake of Sunday’s attack in Orlando, concerns about backlash are greater than ever.

The surveys’ sample sizes are small; each included fewer than 200 participants. Still, the numbers — and the stories behind them — are disheartening. Muslim students said their non-Muslim peers have called them terrorists and accused them of disloyalty to the United States.

The problem extends beyond the Beltway: The MCC survey was modeled on a similar study conducted in California last year, which yielded even more worrying results. There, more than half of respondents said they had been bullied over their religion. One girl’s high school yearbook replaced her name with “Isis.” In Florida last year, a French teacher referred to a 14-year-old Muslim student as a “raghead Taliban” and repeated the insult until the boy’s father complained to the school administration.

Certainly, as the MCC and the ICC recommend, schools should train teachers to make Muslim students comfortable in the classroom. Teachers should share the importance of sensitivity with their students, making clear that racist remarks are not acceptable and checking in with Muslim students who have been targeted.

But the disturbing standard Mr. Trump has set will undermine constructive lessons learned in school. It doesn’t help that Republican leaders endorse the candidate, even as some condemn the worst of his statements.

On Tuesday, Mr. Trump claimed that American Muslims of all generations have failed to “assimilate” to U.S. life and culture. As Post reporter Jose A. DelReal has pointed out, data prove him wrong: Muslim Americans identify with this country as strongly as they do with their faith. But even as Muslim immigrants and their children embrace the United States, Mr. Trump labels them the enemy. Such racist rhetoric is an assault on our values, and — as this year’s surveys suggest — on our children.