The Straits of Hormuz are now temporarily open pursuant to the cease fire agreement.
But if no final agreement is reached during this hiatus, Iran can again threaten to close them to ships from nations unfriendly to them, as it did over the past several weeks.
Iran may have the military power to close the straits of Hormuz to all shipping, but it shouldn't have the power to decide who can go through and who cannot.
The United States should declare that if Iran were again to close the straits to some ships, the U.S. would close it to all ships.
In other words, Iran has the power to decide to close the straits, but it does not have the power to keep it open to selectively itself and its friends.
The U.S. has the power, through a military blockade, to close the straits to all shipping, including Iran's.
Such a total closure would require all the shippers of Gulf oil to find alternative ways of getting it to its customers.
Such efforts are already underway.
Closing the straits to Iranian-approved ships unless Iran opens it to all ships would raise the price of oil in the short term, but lower and stabilize it in the long term, as oil producing companies find alternative routes and deny Iran the power to raise prices by closing one route that accounts for 20% of oil shipments.
Iran's closure of the straits to some shipping is clearly illegal, since the straits are an international waterway with open access to all.
Iran has chosen to engage in illegal action by blocking the straits to some.
It would be entirely lawful for the United States to respond to Iran's illegality by closing the straits to all and conditioning its reopening on Iran's agreement not to pick and choose who can use this international waterway.
This would be tough justice, because those countries now allowed through the straits would be denied access.
But Iran has no right – as a matter of law, policy or morality – to decide who is and is not allowed to use this international waterway.
A partial blockade can be responded to by a total blockade.
The biggest loser would of course be Iran itself, which would be denied the payments it is now getting for its selective permissions.
It would also be denied its own use of the straits to transport its own oil.
Although Iran does not need the straits to transport its oil, since it has access to other waterways to its south, it will still be hurt financially.
That would be a good thing.
I'm not an economist and so it's possible that I'm not considering all the economic ramifications of such a closure, but on its face, it seems like a good idea for the U.S. to impose an all or nothing condition on the use of the straits: all go through, or nothing goes through.
There is also the military option to reopen the Straits and keep it open by force.
But that too has problems.
All it takes is one attack, or even threat, to deter ships from going through.
Closing the Straits by military force or threats is much easier than opening them.
So why not try the all-or-nothing economic threat before deploying the uncertain military and dangerous military option.
If that doesn’t work, the military option is always available.
It's possible, of course, that Iran will decide to keep the straits open to all – at least soon.
But it can always change its mind and close it again on a selective basis.
That is a good reason for the U.S. to announce now that it will never allow Iran to pick and choose who is allowed through.
The all-or-none policy will deter Iran from doing what it did during the recent military action. It will also show the world that Iran does not alone control the Straits of Hormuz.
Alan M. Dershowitz is the Felix Frankfurter Professor of Law Emeritus at Harvard Law School and the author most recently of "The Case for Color Blind Equality in the Age of Identity Politics," and "The Case for Vaccine Mandates," Hot Books (2021). Read more of Alan Dershowitz Insider articles — Click Here Now.
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