They didn’t so much as speak his name, but two top Obama administration officials admonished Republican presidential nominee Donald Trump Wednesday, casting his rhetoric on Muslims as a threat to national security.

Speaking at the Washington Ideas Forum, Homeland Security Secretary Jeh Johnson responded to a question from ABC News White House correspondent Jonathan Karl about whether ISIS is rooting for a Trump victory. (The argument is that Trump’s disparaging comments about Muslims directly benefit terrorists by serving as a recruitment tool for them.)

“I think we should be concerned about rhetoric that has the effect of isolating the American Muslim communities here,” Johnson said, “vilifying Muslims and driving them to a place where our enemies would like them to be, to make them more susceptible to the [ISIS] recruitment effort.”

Johnson told Karl he wasn’t supposed to comment on candidates specifically — “Sometimes that gets hard” — but the idea that Muslims don’t belong in the United States or can’t be American is “exactly what terrorist organizations want them to hear.”

CIA Director John Brennan also got questions on Trump and national security at the forum, in conversation with the Atlantic’s national correspondent Jeffrey Goldberg.

“Making comments that are incendiary and that are viewed as attacking a religion or a people or a community only further drive those individuals to grasp onto those extremist views,” Brennan said. “They interpret a lot of the comments that are made as the West and the United States are against them … It’s the extremist comments on both sides of this have just fed those sources of extremism.”

As a presidential candidate, Trump periodically has called for a ban on all Muslims entering the United States, citing concerns about terrorism. Freedom of religion has historically been a core American value.

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