Whether it is ISIS, or al-Nusra, or Khorasan, there are thousands of jihadists in Iraq and Syria threatening global security. In Syria, the influx of foreign fighters far surpasses anything we have even seen in Afghanistan. The scale of this mass migration is unprecedented and it results in deadly attacks. More foreign fighters have flocked to Syria and Iraq to fight for radical Islamic groups like ISIS in the last 2 years than fought in Iraq and Afghanistan in the last 12 years. According to estimates, around 15,000 jihadists from over 80 countries have traveled to Syria to fight. Two thousand of these killers are from Western countries, including the United States and the EU; 500 are from the U.K., 700 from France, 400 from Germany, and over 100 from America. All of these Western passport holders can travel freely in Europe and even to the United States once they have finished their tour of duty in Syria.