In the Washington Post, Greg Sargent analyzes a pattern in Trump’s very effective rhetoric.

As you’ll recall, after Trump made his “animals” comment, his defenders — and Trump himself — erupted in anger at news organizations that had not explained that it had come amid a discussion of MS-13 members. It’s not clear from the context that he was talking only about MS-13 members. His ramble suggests he might have been referring to the people “we’re taking out of the country.” We can’t really be sure.

But as Julian Sanchez pointed out, this is precisely the point. Even if you adopt the most charitable interpretation — that Trump’s surface meaning was exclusively about MS-13 members — it is still not exonerating. That’s because the conflation of MS-13 members with undocumented immigrants is not an accident stemming from an imprecisely worded statement. The conflation is itself the statement.

Dehumanizing rhetoric works in exactly this way: It slaps the dehumanizing slur on the least sympathetic subgroup and then conflates that subgroup with the larger group that is the real target, then piously feigns innocence of any intention to tag the slur on the larger group. The dead giveaway here, as Sanchez also noted, is that this is a selectively applied technique: When Trump attacks criminals who don’t belong to the out-group he’s scapegoating, no such conflation is in evidence.

I can’t help but think of Martin Niemöller’s oft-cited warning:

First they came for the Socialists, and I did not speak out—
Because I was not a Socialist.
Then they came for the Trade Unionists, and I did not speak out—
Because I was not a Trade Unionist.
Then they came for the Jews, and I did not speak out—
Because I was not a Jew.
Then they came for me—and there was no one left to speak for me.