Lt. Col. Ralph Peters (Ret.) joined Bill O'Reilly on "The Factor" to react to ISIS attacking Iraq's largest oil refinery, plus the terror group's brutal slaughter of 300 captives.

O'Reilly said he gets the feeling that the Obama administration simply doesn't want to hear about ISIS anymore.

"The Obama administration has ignored this problem for so long that a minor problem has become a global problem," Peters charged.

He said that radical Islam was on the run when President Bush left office, but things have changed on Obama's watch.

"We are playing defensive ball, and you can't win that way," Peters said, adding that it's not just the president, it's the whole worldview of the media and the left.

"When you fight monsters in human form, such as these creatures in the Islamic State, Al Qaeda, etc., you better be willing to ... kill them," Peters said.

Watch more above and check out Peters' new Civil War book, "Valley of the Shadow."

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