Dr. Martin Sherman says the heart of the new Israel-Lebanon agreement is simple: Lebanon must restore its monopoly over weapons and force in the south, while the United States acts as guarantor for implementation.

But that goal raises the central question: Can the Lebanese government actually deliver? Sherman compares the agreement to signing a house purchase with a child instead of the parents — because Hezbollah, backed by Iran, still holds the real power on the ground.

If the agreement is carried out, Dr. Sherman says it would be a grave blow to Iran. But he warns that Washington will need to show far more resolve than it has shown until now, especially if it fears that pressure on Hezbollah could complicate President Trump’s wider effort to reach understandings with Tehran.