Raping women and girls. Pedophilia. Sexual enslavement.
Throwing homosexuals from rooftops.
Enforcing ignorance and rooting out knowledge. Slaughtering those of different faiths -- Christian, Jew, Muslim, Sunni, Shia.
Despising all other forms of governance, whether democratic or authoritarian. ISIS doesn't simply "hate our values" -- they hate every value but theirs.
Their adherents have visited death anywhere they can -- the Middle East, Africa, France, Turkey, Indonesia, Afghanistan, the United States.
Far from a "clash of civilizations," ISIS' jihad is against civilization itself. It feeds on, and feeds, alienation and fanaticism.
Its imperatives are non-negotiable, its apocalyptic nihilism beyond the reach of reason.
Its primal loathing of the other cannot be stilled by "carpet bombing" or "declaring war."
It cannot be avoided by withdrawal or wishful thinking, or defeated by bellicose rhetoric.
Inevitably, ISIS has become a significant campaign issue -- particularly important, polls tell us, to Republican primary voters.
The realities of confronting ISIS are diabolically complicated -- perhaps too complex, given the constraints of campaigning, for any candidate to fully describe.
But we can only evaluate their fitness for leadership by first considering those realities, then comparing them to what the candidates choose to say.
To start, any leader who wants to address this scourge responsibly must deal with a harsh geopolitical terrain.
The context for stanching ISIS resembles a Hobbesian state of nature.
Syria, Iraq and Libya are failing or failed states, a condition which -- depending on your point of view -- owes much to our actions, our failures to act, or both.
Thus the theater within which ISIS operates is inhospitable indeed -- a key point in evaluating a candidate's prescriptions for military action.
Syria is a violent and chaotic nightmare riven by contending forces -- the enemies of our enemy, ISIS, are hardly our friend.
Iraq is a fractious mess ridden by a multiplicity of sectarian hatreds and rivalries, including those between and among the Shia, Sunni, and Kurds. Read more: