Article @ The Guardian from April of by Michael Kimmel  who is the author of Guyland and Angry White Men. He directs the center for the study of men and masculinities at New York's Stony Brook University:

Almost all violent extremists share one thing: their gender

Most people who commit acts of terrorist violence are young men. We overlook their gender to our peril

‘Young men often come into extremist movements because they experience downsizing in specifically gendered ways.’ 

According to an ever-growing number of young men in Europe, the United States and across the Muslim world, we are at the beginning of a war. And no one knows how it will end.

To me, what is interesting in the paragraph you just read is not the indeterminacy of the outcome. All crises are like that. No, it is the fact that “ever-growing number of young men” probably does not seem notable to most readers.

The fact is that virtually all of those mobilizing on all sides of this growing clash are young men – whether right-wing extremists, anti-immigrant zealots, anti-Muslim skinheads and neo-Nazis or young Muslims readying for jihad.

It’s so obvious, it barely needs noting.

And so it isn’t noted.

If we imagine for a moment that all those amassing on all the different sides of this looming cataclysm, all those drifting to the edges of the political spectrum and toward violent extremism, were female, would there be any other story? Wouldn’t magazines be filled with individual profiles, TV news shows highlighting the relationship between femininity and violence, bookshelves sagging from the weight of the “gender” analysis?

Yet the fact that virtually every single violent extremist is male creates hardly a ripple.

It can be easy to think: “But wait, what about those female suicide bombers? What about those skinhead girls? Those women of the Klan?”

This proves my point [....]