Former U.S. Secretary of State Henry Kissinger told Sky News that there was no question in anyone's mind on how to deal with Adolf Hitler during World War II and so it should be with ISIS.
"During the Second World War, nobody said, "What is the solution for dealing with Hitler?" Kissinger said. "And this is an organization that has engaged in mass murder on television in the killing of prisoners. So I do not think that the Islamic State as it exists is a group with which we can negotiate."
Speaking further on the matter, Kissinger said:
I don't see any possibility of meaningful negotiation with the Islamic State. I think the Islamic State in its present form has a caliphate to dominate the region and indeed any area where Muslims are living that's incompatible with the international order as we see it. But I can conceive and expect a negotiation taking place between many of the parties in the region to try to create an international order there, minus the Islamic State, that will be more compatible with peace than we've had.
Kissinger added that efforts against ISIS shouldn't fall just on America's shoulders, but, at the very least, should be an "Atlantic effort."
As far as Europe, Kissinger indicated that open-border policies seem like a good thing on the humanitarian end of the spectrum, but with that large of an influx of whole peoples into those countries will inevitably bring large problems. He called the refugee crisis "a fundamental change" never before seen in history.