The Paris terror attacks have brought the issue to the fore in awful, dramatic fashion. It's inevitable that the topic will feature in tonight's Democratic debate and the wider campaign. With world leaders set to convene in Paris in a few weeks time for the global climate negotiations, French vulnerability to terrorism has taken on added significance. While ISIS does not pose an existential threat to the United States, attacks on civilians are a more tangible security threat than potential peer competitors that politicians ignore at their peril. The attacks, which claimed the lives of more...