Before the war, the regime was facing the threat of imminent collapse. But if the war ends without regime change, they may use it as an excuse to eliminate organizers and other key opposition figures. If they have not already done so. If no other options exist, the regime will remain in power, despite the lack of popular support.

As for deterrent, Iran will probably stop being a significant threat to Israel. But cheap drones have changed the situation closer to Iran. The military power required to close the Strait and hobble the economies of the Gulf states is orders of magnitude smaller than the military power needed to stop it.