AP Photo

To most observers witnessing events in Syria, the goal is clear-cut: end the killing, support democracy, and change the Assad regime -- hoping it will be removed or reformed to an unrecognizable degree. State actors looking at the same reality will often bring a different set of considerations into play, especially if they happen to be neighboring Syria. Israel has had a complicated relationship with the popular upheaval in its northern neighbor -- and, indeed, with the Baathist Damascus regime in general over the years.

As of Sunday, that complexity entered a new dimension. Of course the popular uprising in Syria is not about Israel, nor will it be particularly determined by Israel's response. Nevertheless, Israel's leaders, like those elsewhere in the region, will have to...