"Terrorists aren't as inhuman and single-minded as you've been essentially brainwashed into thinking. They have the same motivations as most other human beings."

As a whole, this is true of the leadership. This is virtually true by definition because being that inhuman and single-minded is incompatible with leadership and anybody who tries fails as a leader. Unfortunately, the way they lead is to fire very very potent memetic weaponry around with relatively wild abandon and they do unfortunately end up producing True Believers in quantity. We know this, because a suicide bomber almost by definition has to be a True Believer, and suicide bombers definitely exist. I would tend to agree that most terrorist leadership would rather use the nuke as a stick to beat people with rather than fire it but I am uncomfortable with the scenario in which one or more True Believers come to believe that their leadership are actually traitors and in their True Belief fire the weapon anyhow. Terrorists build their structures around some very toxic and volatile belief structures and we are justified in being very concerned about the combination of that and nuclear weaponry. Perhaps not "terrified" but certainly a matter of justifiable international concern. (I would reserve terrified for 5-15 years in the future when biological warfare becomes easy enough for them.)

It only takes one True Believer.