Japanese militarism grew - and then declined - in the last century.
Nor is this the first manifestation of extremism in Islam. The Kharijite movement of the late 7th Century AD also flourished and ultimately burned itself out.
Things like this come and go in waves; such is the nature of all religions and movements. They wax and wane.
But only after we waged a purposeful, focused bloody war to the death against them, dropped two atomic bombs and imposed a military occupation on them.
Exactly - by force of arms. If the author lived in 1930's Germany, would he be spouting similar nonsense about the "moderate" factions of the Nazi Party?
Having lived in the Muslim world, I know that there are many Muslims that are peaceful. The problem is that, with Islam, the most radical factions predominate, and no one dares oppose them. After all, they are the "most dedicated and faithful" practitioners of the religion.
Also, even "moderate" Muslims can be easily radicalized by what one observed called "the incandescent fury of Islam..." - as in the early flashbulbs that smoldered before igniting. Many Muslims are taught to hate the "infidel" and that violent Jihad against those who oppose their religion is their sacred duty. Thus underneath the "thin veneer" of moderation run dark currents that are unimaginable to the Western mind.