Extremists: Can ISIS be the most dangerous terror group yet?

Eric McClam --- NBC News 

June 20, 2014

The leader of the Islamist fighters sweeping across northern Iraq has been called the heir apparent to Osama bin Laden. But there are big differences between his group - the Islamic State of Iraq and al-Sham - and bin Laden's al Qaeda.

ISIS is a more conventional fighting force, rolling in with tanks and capturing whole cities with brutal force rather than staging spectacular, carefully planned, one-off bomb attacks.

Think of ISIS as more of a Goliath than a David.

ISIS found fertile ground to grow in the civil war in Syria and the aftermath of the U.S. occupation of Iraq. Last week it made a lightning advance across the Iraqi north, capturing large cities. The group immediately ordered women to stay home, banned smoking and drinking and warned of harsh consequences under Sharia or Islamic law.

Demonstrating their growing hold, ISIS militants on Thursday hung black banners on watchtowers at the biggest oil refinery in the country, a critical source of domestic energy.

The ISIS power grab has raised concerns about a wider Sunni-Shiite war in the Middle East.

“They represent a threat to every country in the region,” Secretary of State John Kerry told TODAY in an interview that aired Thursday. “They’re more extreme even than al Qaeda. And they are threatening the United States and Western interests.

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