(Olivia Harris/AP Photo)

Senate Majority Leader Harry Reid today criticized former Vice President Dick Cheney's views on foreign policy, describing his advice to House Republicans as "terrifying."

"Taking advice from Dick Cheney on foreign policy? That's a terrifying prospect. We should be learning from our past mistakes, not repeating them," Reid said on the Senate floor today.

"They've got to be really careful with advice they take from Dick Cheney. Dick Cheney is more responsible than anyone else for the worst foreign policy decision in the history of the country - the invasion of Iraq," Reid said.

Cheney, one of the architects of the Iraq war, met privately with House Republicans Tuesday and discussed the threat that the Islamic militant group ISIS poses to the international community.

According to sources who attended the meeting, Cheney said the president lacks a clear strategy to combat terrorism in the Middle East, a criticism he repeated today in a speech at the conservative American Enterprise Institute.

"There's a connection between a disengaged president and the very volatile situation abroad," Cheney said today, adding that the president has a "distrust of U.S. power as a force for good."

Cheney shared his own vision of a U.S. response to ISIS ahead of the president's speech tonight: a sustained campaign in both Iraq and Syria, including U.S. airstrikes, military trainers and special operations forces.

"Our president must understand that we are at war, and must do what it takes as long as it takes to win," Cheney said.

ABC News' Dee Carden, John Parkinson and Benjamin Siegel contributed to this report.