Trump rebuked a retired Army colonel critical of his take on retaking Mosul, Iraq.
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"I have a very distinct idea as to what I want to do," he added.
The city of Manbij was freed from ISIS control Friday.
"He inflames the debate, and we don't need the flame," Michael Hayden said.
Giuliani said the remark was "legitimate political commentary" and "true."
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"These guys don't know what they're talking about," he said of the Trump-Pence ticket.
The deal is intended to help battle the Islamic State in Iraq and Syria (ISIS).
Screening for radicals does not equate to a "War on Islam."
Video release of disillusioned ISIS fighters a good start
The Syrian fighters are meant to combat the Islamic State in Iraq and Syria (ISIS).
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Obama addresses weekend bombing attacks and stabbing at Minnesota mall
The GOP presidential nominee addresses foreign policy to supporters in Youngstown, Ohio
Clinton's team accused Trump of an "unprecedented lack of knowledge" after his ISIS remarks.
Trump said Obama gets "the most valuable player award" for ISIS.
A federal judge in San Francisco dismissed the suit.
"You have no idea what my strategy on ISIS is," he tweeted at Kelly.
Failed takeover attempt a defeat for counter terrorism efforts.
The types of people Nice has welcomed for centuries were among those who perished.
Steps necessary to right the wrongs of Obama administration
Mohamed Bailor Jalloh met wita an FBI informant he believed to be an ISIS member.
"This is ISIS," Gov. Rick Scott (R-Fla.) said. "This is evil."