Transcript for ISIS forces now cornered in Syria

week" with ABC's Martha Raddatz. Overseas, to the desperate fight for the latest ISIS stronghold in Syria. The human toll, high. The images coming in. James Longman taking us through the scarred towns that make up this battlefield. Reporter: Rubble and dust -- the ISIS legacy. It once spanned two countries and attracted thousands of extremists from all corners of the globe. Tonight, the so-called caliphate is reduced to about 7,000 square feet of freezing mud in southeastern Syria, where 1,000 or so ISIS fighters are in a standoff with coalition forces. Today, we drove out to the towns nearest the frontline. We saw why victory can't be called just yet. You can hear overhead that's the sound of aircraft approaching because they think that ISIS bikes are now on the horizon. When we did arrive, the coast was clear. Every building destroyed. Massive craters from U.S. Airstrikes every few hundred meters. There is no life here. Over 15,000 coalition bombs were dropped on Syria during this anti-isis campaign and you have to ask, have these towns been liberated, or eliminated? In the next town, life is creeping back. Families try to rebuild what they once had. But this will take years. ISIS may be gone, but not much else is left either. When U.S. Troops do go home, as president trump has promised, the so-called caliphate will have been defeated. But large parts of this country have been so badly destroyed, that the roots of extremism may easily take hold again. Tom? James, thank you. Now to historic move by pope Francis, defrocking former cardinal Theodore Mccarrick.

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