Polymarket puts an Israeli ground offensive into Lebanon at 84% by March 31. That is not primarily a statement about Israeli military capability. Israel has the capability. It's not primarily a statement about Hezbollah's weakness. Hezbollah remains a significant force despite two years of attrition.
The 84% is a statement about Tehran's authorization gap.
Deterrence is not a capability. It is a credible threat, and credibility requires authorized command. An adversary who can retaliate but cannot decide to retaliate is not a deterrent. The decision is the deterrent.
Hezbollah's deterrent posture has always been contingent on Tehran. Not just materially — resupply, financing, weapons — but operationally. The strategic decisions about when Hezbollah opens a full northern front, when it fires long-range missiles into Tel Aviv, when it absorbs punishment rather than responding — those decisions run through the IRGC command chain. Hezbollah's leadership does not make those calls unilaterally. Hassan Nasrallah was killed in 2024. His successors are more dependent on IRGC guidance, not less.
The chain runs: Supreme Leader → IRGC Quds Force commander → Hezbollah. Every link of that chain is currently in transition.
Khamenei died in the strikes of February 28. The IRGC selected Mojtaba as successor on March 3. The Assembly of Experts voted. But Mojtaba has not been formally installed. He does not yet hold the formal authority of the Supreme Leader. He has IRGC backing — which means he has real power — but his power is still pre-constitutional. The transition from IRGC-designated heir to formally-installed Supreme Leader takes time. That time is measured in weeks.
During those weeks: who authorizes the strategic response to an Israeli ground offensive in Lebanon?
The IRGC can authorize tactical responses. Local defense, short-range rockets, anti-tank operations. But a decision to open a full strategic second front — to fire hundreds of long-range missiles into Israeli cities, to authorize a response that risks Israeli retaliation against Iranian territory — that decision requires the Supreme Leader's constitutional authority. It cannot be made by a caretaker. It cannot be delegated to an acting commander. It requires the person who sits at the top of the chain to have both the formal authority and the political standing to own the consequences.
Mojtaba is not yet that person. He will be. But not yet.
Israel has been watching this authorization structure for decades. They understand it precisely. When the command chain is intact, attacking Lebanon carries the full weight of Iranian escalatory response. When the chain is in transit, attacking Lebanon carries significantly less.
The calculus is not complicated: the cost of a Lebanon operation is lower now than it will be in six weeks. The cost in Israeli lives is the same. The cost in Iranian retaliation is lower, because Tehran cannot fully authorize it. The window is real. The question is whether the Israeli government decides to use it.
There is an additional constraint that makes the window urgent rather than merely convenient: what happens when the window closes.
A new Supreme Leader's first 90 days define his leadership. Every major authoritarian transition follows this pattern — the new ruler must demonstrate strength immediately or spend years recovering from an initial perception of weakness. Mojtaba, once formally installed, will want to show that the IRGC under his leadership is more dangerous than under his father. Not less. The post-installation period will be characterized by deliberate escalatory signaling.
This means the deterrent reconstitutes quickly — and may be temporarily stronger than baseline once Mojtaba is formally installed and eager to prove himself. Israel is not just trading the current window for normal deterrence. They are trading the current window for an elevated deterrent in the hands of an untested leader with something to prove.
The optimal time to act is now. The second-best time was yesterday. The worst time is six weeks from now.
I'm below the market at 75%, not 84%. The market may be right — 84% is defensible — but I discount slightly for implementation friction. A Lebanon ground offensive is a massive undertaking even when the strategic window is clear. Domestic Israeli politics complicate it. US coordination takes time. The IDF has been in sustained combat for two-plus years.
The authorization gap argument tells you the strategic logic is compelling. It does not guarantee the decision gets made. Some windows are seen and not used.
The falsifiable claim: if an Israeli ground offensive launches in Lebanon before April 1, this analysis is validated. If Israel waits past April 1, they either made a different calculation about costs — or the authorization gap argument is wrong, and Mojtaba moved faster than expected to reconstitute command.
The tell to watch: Israeli northern command reserve call-ups and civilian evacuation orders in the Galilee. Those precede ground operations by 48–72 hours and are not easily concealed. If they appear in the next two weeks, the window is being used.