Last week, President Barack Obama berated Donald Trump and other critics of his refusal to say the words “radical Islam” when describing the terror threat against the United States, including the brutal attack on a gay nightclub in Orlando, Florida.

“[T]here is no magic to the phrase ‘radical Islam’,” Obama said angrily. “It is a political talking point. It is not a strategy.”

But words do matter — as Barack Obama himself told us, back in 2008. Then, he was running against then-Sen. Hillary Clinton (D-NY), who mocked Obama as an neophyte whose only real strength was his ability to make a good speech.

“Don’t tell me words don’t matter,” Obama thundered (plagiarizing Massachusetts Gov. Deval Patrick).

If there were no “magic” to saying the words “radical Islam,” surely there would be no “magic” to avoiding them, as Obama has done.

Words matter — especially those words.

“Radical Islam” defines the enemy clearly and concisely as an extremist subset of a particular religion. The phrase separates radical Muslims from other Muslims, without denying that its inspiration comes from the Muslim world and must therefore grapple with complex theological questions, as well as the limits of Western tolerance.

Muslims themselves understand this. Last year, on New Year’s Day, Egyptian President Abdel Fattah al-Sisi stood before his country’s religious leaders and spoke, clearly and courageously, about the need to articulate the religious basis for a struggle against those radicals who had abused Islam to bring terror to the world:

Among other things, Sisi said that the “corpus of [Islamic] texts and ideas that we have sacralized over the centuries” are “antagonizing the entire world”; that it is not “possible that 1.6 billion people [reference to the world’s Muslims] should want to kill the rest of the world’s inhabitants—that is 7 billion—so that they themselves may live”; and that Egypt (or the Islamic world in its entirety) “is being torn, it is being destroyed, it is being lost—and it is being lost by our own hands.”

To deny that we, and Muslims like President al-Sisi, share a common enemy in radical Islam is to deny the essential nature of Islam al-Sisi seeks to restore.

Worse, the denial of “radical Islam” — which is replaced by euphemisms such as “combatting violent extremism” — has far-reaching negative consequences throughout law enforcement agencies and society itself. In several cases, ordinary citizens who were suspicious about future terrorists’ behavior have been ignored — or were silent — because of political correctness.

“Don’t tell me words don’t matter!”

Don’t tell us, either, Mr. President.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. His new book, See No Evil: 19 Hard Truths the Left Can’t Handle, will be published by Regnery on July 25 and is available for pre-order through Amazon. Follow him on Twitter at @joelpollak.