richardsilverstein.com:

Within Syria there are many factions: the regime, Iran, the Russians, and even al-Qaeda and ISIS.  In such circumstances, one must develop a responsible, carefully-balanced policy by which you protect your own interests on the one hand, and on the other hand you don’t intervene.  Because if Israel does intervene on behalf of one side, it will serve the interests of the other; which is why we’ve established red lines.  Anyone who violates our sovereignty will immediately feel the full weight of our power.  On most occasions, firing comes from regions under the control of the regime.  But once the firing came from ISIS positions–and it immediately apologized.

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