A British preacher is accused of recruiting hundreds of Muslims for the Islamic State of Iraq and Syria, known as ISIS.
Abu Rumaysah converted to Islam from Hinduism and wants to see the spread of strict Islamic Sharia law throughout the world. On Sunday night's "60 Minutes" Clarissa Ward interviewed Rumaysah.
"The foreign policy ... is to expand the borders of the Islamic state," he said. "So very soon, my dear brothers and sisters, we're going to see the Khilafah expand into Jordan, into Saudi Arabia, onto the shores of Europe. And one day Obama, he will witness his own country be run by the Sharia."
"So I do believe one day that America and Europe will one day be under the Sharia," Rumaysah continued. "And I think that is a blessing. However, I would also say that in the short-term, the Americans and the British, they need to be very wary."
While his views are shared by a small group of Muslims, they are a vocal minority whose plan to expand Sharia law can be a frightening prospect to many around the world.
"I understand that many people are unaware of the Sharia and the blessings it can bring," he said. "The Sharia is not there to subjugate non-Muslims, it's there to liberate them."
Rumaysah said he can't travel to Syria or Iraq to live in the ISIS-controlled caliphate because the British government monitors his travel.
But as Ward pointed out, many of the extremists are happy to stay in the U.K. and enjoy a comfortable and free life while they call to an end of democracy.