Marines are called Leathernecks because they wore leather cuffs around their necks to keep from being beheaded by Muslim pirates.
There will never be peace with Islam.
Aggression is part of the religion and is written in their book.
Peace is an illusion. Yes, it's a proper goal, but it is impossible in the long run.
The only way to end this violence is to end Islam.
The people are not the problem, if they can be separated from Islam. Or if Islam can be reformed.
Good luck with that.