US special operators are quietly avenging the attacks in Paris and Brussels

ISIS spends a lot of time celebrating their attacks on foreign soil, making them seem like overwhelming victories in their global campaign of fear. Meanwhile U.S. special operations forces in Iraq and Syria have killed 40 ISIS fighters responsible for those attacks.

Officials from the Department of Defense told Kim Dozier of The Daily Beast that U.S. special forces have killed those "external operations leaders, planners, and facilitators" who were part of those attacks outside the CENTCOM area of responsibility.

The use of special forces in kill or capture raids (though the capture part tends to happen much less frequently) is a major part of the U.S. counterterrorism plan against ISIS. Those 40 are less than half of the high-value targets that coalition forces have taken out. The U.S. mission also includes curtailing the terror group's ability to recruit abroad and inhibit their ability to carry out Paris-style attacks. President Obama has ordered 250 more special operators to Iraq to support these operations.

According to Dozier's report, the effort is seeing results. Those same defense officials estimated that ISIS' overall fighting force is down to 19,000 - 25,000 fighters, from 33,000 in 2015. Moreover, the influx of new recruits coming into the region is down 90 percent from last year.

Dozier also reports that the Director of National Intelligence Jim Clapper warned this week that ISIS cells are already in place throughout Europe. ISIS' external operations have killed 1,000 people across 21 countries since 2015. But the U.S. Joint Special Operations Command (JSOC) is using a mixture of special operators from many, varied disciplines. Their units include Navy SEALs, Delta Force, and Green Berets integrated in all aspects of the JSOC mission. This ensures the highest performers are on kill-capture raids, and have experience in hostage rescue and working with local opposition forces.

This may be a product of battlefield lessons learned. These days, the CENTCOM AOR is run by Gen. Joseph Votel, who once commanded both U.S. Special Operations Command and JSOC. Lt. Gen. Austin S. Miller, the current JSOC commander, ran special operations in Afghanistan, where he used the mixed special forces tactics with great success.