How many Muslim extremists are there? Just the facts, please.

UPDATE, Nov. 19, 2015: Conservative lawmakers and activists across the world have renewed their accusations against Muslims in the aftermath of the recent terror attacks in Paris.

That Abdelhamid Abaaoud, the militant suspected of plotting the attacks, went to Syria last year to fight with the Islamic State has only heightened their fears of the reach of jihadists. Mr. Abaaoud, a Belgian citizen, died in a police raid in the Paris suburb of St. Denis early Wednesday.

This story originally ran Jan. 13 in the wake of the deadly jihadist attack on the Paris office of Charlie Hebdo, a satirical magazine. 

ACT! for America's president and founder Brigitte Gabriel has become a media favorite of conservatives concerned about terrorism. A video of Ms. Gabriel's comments about "Muslims dedicated to the destruction of Western civilization" at a Heritage Foundation forum in June 2014 was revived by bloggers and passed around social media. 

"The radicals are estimated to be between 15 to 25 percent, according to all intelligence services around the world," she said, in part, when asked by an American University head-scarf wearing law student about waging an ideological war with Muslims. "You're looking at 180 million to 300 million people dedicated to the destruction of Western civilization," Gabriel added.

Is this figure accurate? 

Not according to Angel Rabasa, who is a senior political scientist at the RAND corporation. While conducting research for a 2014 book he coauthored, "Euro Jihad," he found that Western European intelligence agencies estimated that less than one percent of the Muslim population living within their borders are at risk for becoming radicals.

Note that this is an extrapolation of estimates gathered in Europe; Gabriel’s claim refers to a percentage of Muslims worldwide. That total number is more than 1.6 billion, according to the Pew Research Center. 

Working off of these intelligence estimates, if you were to take one percent of the Muslim populations of Germany, France, and the United Kingdom, by the most liberal of estimates, less than 125,000 Muslims living in these combined countries would be prone to radicalization. Add that to the possible radical population across the rest of Europe and the sum is approximately 325,000 Muslims are at risk of becoming radical. 

The key qualifier is "at risk of becoming radical."  That doesn't mean they will pick up a gun or start plotting an attack.

"Radicalization and violent extremism are two different things," Mr. Rabasa says. "Violent extremist behavior only comes about if a radicalized individual falls in with a circle of people who are open to using violence." 

According to Rabasa, a "radical" Muslim could also be an individual who belongs to an Islamist organization that is advocating for a Sharia legal system, but does not embrace violence to bring this to fruition.

Calls and emails to Act! for America in January to clarify Gabriel's statistics and statements were not returned. 

Perhaps a better indicator to evaluate what percentage of the European Muslims are extremists prone to violence may be to count the number of people who have gone off to fight in Syria and Iraq for any one the thousand-plus factions on the ground, most notably the Islamic State, because these individuals are engaging in combat and are receiving training. 

The Christian Science Monitor reported in September 2014 that the top European Union counter-terrorism official estimated that roughly 3,000 Europeans had gone to fight in Syria, although this figure also counted the dead and was later reduced to 2,000. American officials originally said there were more than 100 Americans who had gone to Syria. But the FBI chief has since reduced it to 12 confirmed people. 

More recently, the number of Europeans that have gone to fight with Islamist militia in Syria and Iraq has been estimated at over 5,000. France is the largest exporter of jihadists. More than 500 French nationals are believed to be fighting there, The Associated Press reported in November 2015.