Iran’s nuclear program and Syria’s civil war may seem unconnected, but in fact they are inextricably linked. Israel’s real fear — losing its nuclear monopoly and therefore the ability to use its conventional forces at will throughout the Middle East — is the unacknowledged factor driving its decision-making toward the Islamic Republic. For Israeli leaders, the real threat from a nuclear-armed Iran is not the prospect of an insane Iranian leader launching an unprovoked nuclear attack on Israel that would lead to the annihilation of both countries. It’s the fact that Iran doesn’t even need to test a nuclear weapon to undermine Israeli military leverage in Lebanon and Syria. Just reaching the nuclear threshold could embolden Iranian leaders to call on their proxy in Lebanon, Hezbollah, to attack Israel, knowing that their adversary would have to think hard before striking back.

That is where Syria comes in. It is the strategic relationship between the Islamic Republic and the Assad regime that makes it possible for Iran to undermine Israel’s security. Over the three decades of hostility between Iran and Israel, a direct military confrontation has never occurred — but through Hezbollah, which is sustained and trained by Iran via Syria, the Islamic Republic has proven able to threaten Israeli security interests.

The collapse of the Assad regime would sunder this dangerous alliance.