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MARIE HARF, U.S. STATE DEPARTMENT: I think there are a few stages here, right now we are trying to take their leaders and their fighters off the battlefield in Iraq & Syria, that is where they really flourish.
CHRIS MATTHEWS, MSNBC: Are we killing enough of them?
MARIE HARF: We're killing a lot of them. And we're going to keep killing more of them. So are the Egyptians and Jordanians, they're in this fight with us. We can not win this war by killing them. We can not kill our way out of this war. We need in the medium and longer term to go after the root causes that lead people to join these groups, whether it is lack of opportunity for jobs--
CHRIS MATTHEWS: But we're not going to be able to stop that in our lifetime or in fifty lifetimes. There's always going to be poor people. There's always going to be muslims, and as long as the trumpet is blowing they'll join. We can't stop that, can we?