I've contended since 9/11/01 that the US needed to resurrect Project Phoenix, worldwide, not just in Iraq. Sort of like the Israelis did after the murders by muslims at the 1972 Munich Olympic games. It took Israel some 20 years to hunt them all down, but they did it. Do we have the fortitude and stamina to do that? Phoenix was effective in SEA, it could be effective now, even if implemented regionally at first, say in Iraq, Syria and Iran. The problem we have, as in SEA, is that we (Americans) cannot discern muslims who need to be killed from those who are "innocent", although the latter term is only relative among those people.
No problem as long as we understand that the shooters may very well be settling personal grudges.