Should the IDF reach the likely conclusion that combatants from the pro-Assad camp - either the Syrian army itself, Hezbollah, or someone acting on their behalf - is responsible for the firing of an anti-tank missile at an Israeli truck, it is difficult to imagine Israel sitting on the sidelines and failing to act to punish the aggressors and restore its deterrence.
The IDF Northern Command is permitted to launch limited, pinpoint responses to border attacks such as this, and this occurred in the form of tank fire on positions held the Assad military on Sunday. But the unprovoked attack is deeply disturbing to senior IDF command, and a failure to launch a more forceful Israeli reply will probably be seen by those responsible as a green light to continue, an outcome the defense establishment will seek to avoid.
Israel has already proven that it would not hesitate to strike Syrian military targets in response to cross-border fire, as it did in March, when it retaliated to a border bombing of an IDF patrol that injured four soldiers traveling on the Golan Heights.
During those air strikes in March, Syrian army command posts, artillery batteries, and a training base on the Syrian side of the Golan Heights were hit.
Speaking after Israel's retaliation, Defense Minister Moshe Ya'alon said the targets struck were chosen because they "allowed and assisted yesterday's terror attack. We will not tolerate any infringement of our sovereignty or harm to our soldiers and civilians. We will respond resolutely and powerfully to anyone who acts against us, at any time and place, as we've done tonight."
There is little reason to doubt that Israel will not follow the same model for action now, and in doing so, deliver a firm message to the attackers, that if they escalate the situation further, they will regret their decision.