Lt. Colonel Ralph Peters (Ret.) joined Stuart Varney on "Your World" today and said that the U.S. needs to strike ISIS both militarily and financially to defeat the brutal terror group.

First, Peters said, we have 2,000 years of evidence of what it takes to defeat fanatical religious insurgencies. We must directly kill as many members of ISIS as possible, according to Peters, to eliminate the hard-line militants and drive out the fringe.

It doesn't have to be America alone, though, Peters stated, but we must take the advantages of our status as a superpower to lead and galvanize the rest of the world.

"The fundamental problem now, in purely business terms, is that Islamic state thinks global wholesale, and we're doing local retail," Peters said, adding that ISIS takes what they want and will not be happy without a major state of their own.

"This cancer has metastasized far beyond what the White House had hoped, and it's not going to get better on its own. We either act or the price goes up."

Watch the clip above.

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