Although current U.S. leadership refuses to define this and does not acknowledge it is happening, the U.S. and the world is experiencing the rise of Apocalyptic Islam.
Western leaders have been blindsided by it, think 9/11 also Paris terrorist attacks and so on, and struggle to understand it; but it has killed thousands and is continuing to kill.
Apocalyptic Islam is the Islamic theology that believes in their End of Days prophecies of their messianic Mahdi who will be revealed on Earth as he establishes his global Islamic caliphate and imposes sharia law.
And they believe that the Mahdi will come only when the world is engulfed in chaos and carnage, and they believe it their responsibility to accomplish this and thus hasten the coming of the Mahdi. They believe that Allah is with them, that they will be greatly rewarded for their actions, and that victory is assured soon.
These beliefs run deep throughout the Islamic world desiring their Mahdi and their global sharia caliphate. It is not only believed by individual Islamic terrorists but also by nation states as Iran and Islamic State. Whose slogans and policies support the practice and implementation of Apocalyptic Islam.