The bestial attacks on Paris last night were a game-changer. We must all recover from our unfocused anger and decide what the right response from the civilized world should be for these--barbarians is too good a word--monsters with evil intent.
I would assume that the domestic counterterrorism will swing into action in France and in other European countries to which the authorities can trace the routes of those who committed these heinous deeds. The circle, hopefully, will expand to the point that other attacks this cell may have had in planning will be intercepted and precluded.
The question remains, though, how to prevent further atrocities, and the only way to address it is to go to the source, the regions controlled in the failed states of Syria, Iraq, and Libya; the places where the leaders of ISIS believe they can act openly. Indiscriminate bombing, cruise missiles, even tactical nukes, or just "bomb the shit out of them" (as Donald Trump suggested even before the latest events)--I'm sure they will all be suggested in the coming days, and it's not that they are not deserved for those who hide there, and I'm not even all that sympathetic to those who have accepted to live among those of ISIS. I just don't think it would work--the cancer would reappear, in a new and even more malignant form, as has occurred in the past after the destruction of al-Qaeda and the collapse of government control in those countries.
As it happens, the G-20--the leaders of 20 major nations--will gather in Antalya, Turkey--only a few hundred miles away from the center of ISIS' depravity--this Sunday and Monday. All the major players will be there (President Hollande of France has cancelled, but will send his Foreign Minister). I suspect the concerns about the global economy will recede under the circumstances, and the focus will be on a unified response. Of course, there will be a communique with a condemnation of the murders, but that is not nearly enough. The response should include: 1) humanitarian aid, for Turkey, Jordan, liberated portions of Syria, and those portions of Europe which have borne the brunt of migrating refugees; 2) a quarantine, a "cordon sanitaire", around the worst-affected areas, to prevent unauthorized movement out (as though jihadists were afflicted with a deadly disease); and 3) a military plan, a broader coalition of the willing, with the objective of going beyond merely containing ISIS but to the physical elimination of its lawless "safe area".