You probably haven’t heard of the Umayyad Caliphate, which in itself is a testimony to the effectiveness of its defeat. But there was a time when the Islamic Umayyad armies had taken over a huge swath of the ancient world, reaching from India all the way to the Iberian Peninsula. That’s where Spain is. In fact, the Umayyad armies were set to conquer all of Europe, and they would have, largely but for one man: Charles Martel. He defeated the Umayyad armies at the Battle of Tours, and Islamic power reached no further into the West.

But now, ISIS is making inroads into North Africa, is resuming the ancient territories of the old Islamic Caliphates, and is poised to conquer Europe from the inside. The recent North African expansion of ISIS is quite troubling, as it mirrors the expansions of the Umayyad armies. Beginning with Syria under the Rashidun conquests, Islamic power spread eastward and westward, paralleling the recent successes of ISIS.

What are we to make of this resurgence of radical Islamic power? And what can be done to stop it? Concerning the first question, it seems that, as it was during the Umayyad Caliphate, an ideological and/or political vacuum has crept into Europe and the Middle East. Wherever there is a vacuum, stronger passions will always hold sway. The Umayyad Caliphate gained power because they cared, and very few others did.

Unfortunately, we are missing a key ingredient to our resistance—true grit. ISIS could very well finish what the Umayyad armies were unable to: the conquest of the European west. And the only thing stopping them is a few people with an actually competing worldview. Humanist materialism is not a competing worldview. It is as much a vacuum as the tepid apathy that fell before the Umayyad Caliphate before Charles Martel finally held some ground. Let’s hope men like that still exist, even if they have and always will be in short supply.