Terrorists are to never be negotiated with. Any attempts of negotiation shows a weakness and they will exploit that. Also, any funds delivered to them will be used to fuel their cause (i.e., terrorist camps, weaponry, black market, etc.) To a group who doesn't understand the meaning of diplomacy will not understand negotiations. Al Qaeda, for example, is to make a unified "Islamic world" according to their standards. Those not living to their standards are already labeled targets. They will continue to strike and use all means necessary to keep themselves noticed, or, till their cause it met. Continual deception, influence by force, secret funds, and endless amounts of believers will continue to support their cause.
The terrorists favorite target is the uneducated and the poor. They use various methods to subdue their victims with money, power, drugs, and religion. Most of the terrorists that are not on the high value target list lack education and money. A well educated mullah impostor can preach whatever he pleases and state it is in the Koran. That everything they do is "God's Will." They take these uneducated men, women, children and surround them with wealth physically and spiritually. Opium is a big target for the terrorists which is used in mind technique. With this drug, it is easier to manipulate their cause. Promises of riches to their families for becoming a "martyr" turn out to be false. The ones you hear of are used as propaganda through media outlets who support their cause.
I could go on and on about the whole scheme, but it is best if you read for yourself. There absolutely can never be negotiations with terrorism. Foreign or domestic.