I suppose that depends whether you believed in MAD.

The unspoken premiss of MAD is that your opponent doesn't want to die. On the whole, this was likely to be correct. Both western and communistic ideologies grew out of the Englightenment, which held that life was better than death.

But we are now one coup away from nukes ending up in the hands of people who don't play by those rules.  At least some of them will not mind using them, because they do not fear being killed in the retaliation. Our best hope is that the top guys are more inwardly fearful than the foot soldiers, and can keep them in line.

That still seems pretty scary to me.