Story highlights McMaster still hopes to persuade Trump to soften his rhetoric on the issue

McMaster's argument was that militants, like members of ISIS, are not representative of Islam

Washington (CNN) President Donald Trump warned of "radical Islamic terrorism" in his address to Congress Tuesday night -- despite pushback from his national security adviser.

Newly minted national security adviser Lt. Gen. H.R. McMaster urged Trump to leave the reference to "radical Islamic terrorism" out of the speech, according to a senior administration official. The two men had a discussion about it but Trump decided he would do it anyway.

The senior administration official added that McMaster still hopes to persuade Trump to soften his rhetoric on the issue in the days to come.

This was not a clash, the official said, but a discussion.

In the end, Trump told Congress Tuesday evening: "We are also taking strong measures to protect our nation from radical Islamic terrorism." He then spoke of the threat of violent extremists coming from overseas, citing attacks perpetrated in the US and Europe.

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