WASHINGTON - In the wake of the deadly attack in Nice, former US House speaker Newt Gingrich has called for deporting everyone in America with a Muslim background who believes in Sharia law.

“Western civilisation is in a war. We should frankly test every person here who is of a Muslim background and if they believe in Sharia they should be deported,” Gingrich told Fox News’ anchor Sean Hannity.

“Sharia is incompatible with western civilisation. Modern Muslims who have given up Sharia — glad to have them as citizens. Perfectly happy to have them next door,” Gingrich added. Further, he said: “Anybody who goes on a website favouring ISIS or Al-Qaeda or other terrorist groups, that should be a felony, and they should go to jail. Any organisation which hosts such a website should be engaged in a felony. It should be closed down immediately.”

Gingrich also said that the attack in Nice is the “fault of Western elites who lack the guts to do what is right, to do what is necessary,” and suggested that mosques in America need to be monitored.

Analysts say Gingrich’s proposal, which made no distinction between US citizens and non-citizen, would violate scores of First and Fourteenth Amendment-based Supreme Court rulings and laws that together bar discriminating on the basis of religion, favouring one religion over another by the government and restricting freedom of expression and belief.

Specifically the First Amendment reads: “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.”

In addition, the Supreme Court has ruled that the government has no power to strip people of their citizenship, which would be necessary to deport anyone who is a citizen.

Apart from that, there are an estimated 3.3 million Muslims in the US, according to a recent Pew Research survey who, by Gingrich’s proposal, would have to take his “test”.

Nor is there any evidence suggesting a link between a “belief in Sharia” law and acts of terror in the US, it was pointed out.

“Look, the first step is you have to ask them the questions,” Gingrich said. “The second step is you have to monitor what they’re doing on the internet.

The third step is — let me be very clear — you have to monitor the mosques. I mean, if you’re not prepared to monitor the mosques, this whole thing is a joke.” Gingrich has been mentioned as a potential vice-presidential running mate with Donald Trump, who after the Nice attack called off an announcement of his choice originally scheduled for Friday. Gingrich’s suggestion goes beyond anything suggested even by Trump, who has called for a moratorium on Muslim migration.

The Council on American-Islamic Relations condemned the attack in Nice as well as Gingrich’s call to “test” and deport Muslims in the United States.

“When former House speaker Newt Gingrich suggests that American Muslims be subjected to Inquisition-style religious test and then expelled from their homes and nation,” CAIR National Executive Director Nihad Awaid said, “he plays into the hands of terror recruiters and betrays the American values he purports to uphold.”

In 2014, at a terrorism conference in New York, FBI Director James Comey downplayed the roles of mosques in connection with terrorism.

“I actually don’t see religious institutions as a central feature of recruitment in the United States,” he said. “I see it increasingly as an online phenomenon without centre, which makes it very difficult for us.”

People attracted to terrorism “can get all they need on the Internet,” Comey said.

In the recent terror attack in Orlando, Comey has said that the shooter was radicalised online.

Gingrich also alluded to the long debated “Clash of Civilisations” debate during his interview on Fox News: “These people are opposed to our way of life, they are opposed to our value system, they are opposed to our various religions, they are opposed to the whole concept of freedom …” he said.