Nothing you've thrown at them militarily to date has worked or prevented the many previous attacks or this latest one.
You kill them here-they don't care. Engage them on their land's on a large scale and they would love that even more because it means they kill more of us, or rather you military servers. Its exactly what they want.
And then they will retaliate even further, here.
Only key intelligence, interdiction, practical and intelligent screening and possibly some internment even may work but at massive cost to us in civil liberty, money and blood to stop further outrages.
I knew these days would come, and now they're here.
Self fulfilling, continually revolving cycle of violence.
I would go in the direct opposite of violence to meet ISIL.
Note to western peoples -on this issue think less with balls and use the brain more.