Israel’s approach to ISIS is straightforward. Israel seeks to persuade ISIS not to attack it by credibly threatening to retaliate. If you attack us, the thinking goes, we will respond in ways that will impose pain that exceeds any gain you can hope to achieve. As Cold War strategists learned, making this work in practice is demanding. To be effective, deterrence requires three Cs: clarity, capability and credibility. Specifically, this means clarity about the red line that cannot be crossed, communicated in language the adversary understands; capability to impose costs that greatly exceed the benefits; and credibility about the willingness to do so.
http://nationalinterest.org/feature/why-isis-fears-israel-17286
