Oh, boy! Have not got time to read 140 posts, so apologies if my comments duplicate anyone else's arguments.
I'd better say one thing before starting, I don't like Islam anymore than I like Judeao-Christianity, so I'm not presenting my arguments to convince someone that Islam is 'good.' I'm just trying to see the other side of this issue.
First, we've all had a bit of experience in attempting to convince someone that dying for YHWH/JESUS is an OK thing to do.
So, have you ever thought that if you were trying to convince some young (or older) guy that it would be an OK thing to die for Allah (who is more or less the same YHWH that we once thought it a good thing to die for), what would you say?
For my part, I think I'd raise the point that the west scream their heads off when a few people get killed, but usually do not get upset when anyone in a Muslim nation gets killed. That bastion of freedom and justice, the USA can kill a few kids with a drone strike aimed at some insurgent leader and non-one cares.
I could explore that a bit and ask them to check some history, and make sure that the first time bombs were dropped from a plane onto civilians was during the Christian Italian invasion (and takeover) of Libya (circa 1911). And, that the first time civilians were machine-gunned by an aircraft was during the British take-over of Iraq following WW1, when a champion of freedom and justice named Winston Churchill authorised the RAF to machine gun dissenting villagers who resisted the British occupation of their land (Same old story, the Brits need the Iraqi's oil to power their battleships - newly converted from coal fired to oil burners). I guess a few people protested in the streets of London, but apparently not enough to deter Churchill.
I could go on and on with stories like that - eg. The French army torturing Algerians during the Algerian resistance to the French. And onto the very flawed decision in recent years to invade Afghanistan and Iraq - but even before the 2001 invasion, the USA was interfering in Afghanistan as part of the CIA's cold war operations. When Russia invaded a guy called Charlie Wilson persauded the US government to begin arming the Mujahideen - and you could say that was the start of the huge growth of supplying modern weapons to Islamic forces.
So I'd be telling these young guys, that the only people that seem to be getting hurt are Muslims, is that fiar? Is that Just, Do you love Allah? What are you going to do about it, and some kids/adults fall for it.
As reasoning adults - we need to ask, does all the blame lay on one side?
Don't think I'll go on further, just inviting people to think about it. Don't forget also that other Muslims (probably more so than westerners) are often the victims of Muslim terrorism.
And, one final point, the UK Guardian has recently published this refutation that all Muslims support terrorist tactics.
Link: https://www.theguardian.com/world/shortcuts/2017/mar/26/muslims-condemn-terrorism-stats?CMP=soc_567
The 712-page Google doc that proves Muslims do condemn terrorism
When a classmate told 19-year-old Heraa Hashmi that “all terrorists are Muslims” she began to compile a dossier of all instances of Muslims condemning terror attacks