In the wake of the Charlie Hebdo attacks, the French are searching books on Islam

What unexpected consequence do the events of 9/11 and the Charlie Hebdo attacks share?

Both were tragic events followed by a surprising spike in the sales of books about Islam.

Books on Islam are selling out in France after the January 7 Charlie Hebdo shootings, reports the AFP. The shootings horrified a nation after two Muslim gunmen opened fire on a French satirical magazine and a Jewish supermarket, leaving 17 dead.

Why the rise in interest in Islam? It's a phenomenon the publishing world has seen after 9/11, as well as other tragedies that have drawn attention to and raised questions about Islam and its followers.

“The French are asking more and more questions, and they feel less satisfied than ever by the answers they’re getting from the media,” Fabrice Gerschel, director of Philosophie magazine, which published a special magazine supplement focused on the Quran that flew off the shelves in France, told the AFP.

Consider this: Sales of books about Islam were three times higher in the first quarter of 2015 compared to the same time last year, according to the French National Union of Bookshops.

In 2014, twice as many books were published about Islam as Christianity, according to the Hebdo Livres publishing weekly.

Individual publishers have also confirmed the rise in interest.

Mansour Mansour, who runs the Al Bouraq publishing house which specializes in books on Islam and the Middle East, said sales have increased 30 percent since the attacks.

"The same happened after the September 11 attacks in 2001," he told the AFP, adding, "Now the spike is likely to last longer because Islam will continue to pose a geo-political problem."

That's because of forces such as the Islamic State (ISIS), whose brutal tactics and surprisingly rapid power growth has caught much of the Western world off-guard – and renewed its curiosity in the faith ISIS fighters and those behind the Charlie Hebdo attacks profess to share.

Which is precisely why people are buying books and magazines about Islam: to get a better understanding of the faith some terrorists claim to represent, and to make up their own minds about its beliefs.

As Yvon Gilabert, who runs a bookshop in Nantes, western France, told the AFP, "A very Catholic lady came to buy a copy of the Koran, because she wanted to understand for herself whether or not (Islam) is violent religion."

While the motivation is tragic, observers are turning to the right source – books – for answers.