A short and powerful piece, this, from Nir Eiskovits. Two highlights:

At this point we should introduce an uncomfortable but crucial distinction: terrorism, like guerilla fighting more broadly, is a way of behaving rather than a group designation. Scholars such as Stephen Nathanson have pointed out that it is more coherent to talk about terrorist methods than about “The Terrorists”. These methods are used, disproportionately, by non-state actors like the Taliban, Hamas and (recently) ISIS. But not exclusively. If terrorism consists in the intentional targeting of civilians, then blowing up buses is terrorism, shooting rockets into civilian neighborhoods is terrorism, retaliating in kind is terrorism, and the devastation of German cities at the end of World War II counts as well.

And this:

Refusing to “negotiate with terrorists” is the same as telling our soldiers that we will never talk to their enemies, which amounts to telling them that they have nothing to hope for if they are caught, which is the same as telling them that we don’t “have their back”. That is wrong (for obvious reasons), bad for morale, and catastrophic for our ability to recruit fighters. If any of our asymmetrical wars are worth fighting (a different question altogether), we need to face up to the moral and practical realities involved. We must, in other words, confront the enemy we find, not the one we would have fashioned for ourselves.