Better yet to study the relationship between testosterone and violence; for testosterone has been the driving force behind every war, incursion, mandate, and massacre for centuries.

Check what ISIS (goddess) stands for and figure why was adopted - It's not about islamization and radical Islam but social justice in carved across ethnic/religious lines banthustans by withdrawing colonial powers and replaced by their puppets with few living in splendor and the rest in dark ages. The end justifies the means ... put yourself in their shoes, those hundreds of millions that are left behind, if this has to be done and that's the only way than don't be surprised that they went for it ,...

Islamic colonialism is root cause of 95% violent conflicts in the world today. The many thousands of Islamonazis from the West who joined ISIS are not impoverished or disenfranchised in any way other than of their own volition. Other than Islamic incitement the Boston Jihadist bombers had no grievances against the US that accepted them with opened arms and gave them every possible opportunity. The same applies to Fort Hood massacre Jihadist Nidal Hassan. There are 2 billion non-Muslim people that are much more impoverished and disenfranchised yet they don't engage in anywhere near the violence, mayhem and massacres Muslims commit.

How can Levi Brackman compare his perhaps Chabad passion and fervour to ISIL or similar Islamist groups? Which Jewish leaders call on Jewish youth to murder whomever disagrees with them? Which Christian leaders call on Christian youth to murder other religious groups? ISIL and similar groups are today's barbarians and enemies of Western civilisation. They transgress the Seven Noahide Laws, such as the prohibition on murder.

Sure, testosterone is at the base of most human violence. But without it we won't have humanity. so now - what? Your move. OH! Check mate.