The basic calculus is Iran can close down the Straits and damage the world economy for a brief while, until other sources are brought into play. One of which may simply be to create a military solution that prevents Iran from closing the Straits.
On the other hand, the US can blockade the Straits and stop 70% of Iran’s oil exports, fundamentally destroying the Iranian economy. Iran’s best defense against that happening is the mid terms. But that ends in a few months and the closer we get to the political consequences being baked in, the less constraining the mid terms are.