Trump made vulgar remark about the Kurds during Oval Office briefing: New book
(Official White House Photo by Shealah Craighead)

Donald Trump caught his own national security adviser and a group of Republican lawmakers off guard when he asked why he should "give a f---" about Kurds in Syria who were under threat from ISIS, according to a new book by former GOP Rep. Adam Kinzinger.

“I left with two lasting impressions. One was the despairing look on [adviser John] Bolton’s face as Trump kept struggling to focus. The other was when Trump said of the Kurds in Syria, ‘Why would I give a f---?’” Kinzinger writes in the book, of which The Guardian obtained a copy.

News reports at the time highlighted then-President Trump's decision to abandon Kurdish fighters in Syria and how he rationalized it as part of a campaign promise to withdraw from "endless war" in the Middle East.

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Even some of Trump's most loyal Republican allies expressed outrage at the prospect of abandoning the Kurds, who had received support from the U.S. to fight against ISIS.

Sen. Lindsey Graham (R-SC) had called it a "shot in the arm to the bad guys."

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After retiring from Congress, Kinzinger founded Country First, a group meant to combat extremism within the GOP. His book, Renegade: Defending Democracy and Liberty in Our Divided Country, will be published next week.

Read more at The Guardian.