ISIS have a distorted and pernicious worldview that, on the level of fundamentalism and radicalism they are on, allows very little room for peace or civilized negotiation. They believe that they need the entire world population to convert to Islam and having this idea deeply ingrained into them through indoctrination does not allow much room for different ideas. They will not listen to an opposing worldview and as a result negotiation is impossible.
They threatened to attack Washington, and they sent out a kill list of states they want to attack. If that doesn't mean war i don't know what does. Obama still wants to take in refugees even though they threatened to attack Washington and numerous other states, there is a very high chance that one of the refugees could be trying to fulfill the plan.
I don't have the time nor effort to write a lengthy argument, but i'm just playing devil's advocate. If someone would like to challenge the devil in me, I'll try my best to show no bias and attempt to play the devil's advocate in this scenario.
I don't necessarily have a choice, Yes or no but for the sake of argument i'll try to uphold "no" as my response.