A good rule of thumb for dealing with Iran is to always remember that the Islamic Republic is not a normal nation, guided by the rule of law. When it detains foreign nationals, they are not prisoners awaiting due process. They are hostages to be traded for concessions -- by a regime founded by hostage takers.
This really should go without saying. But evidently Britain needs a reminder. Take the latest "scandal" involving a minister in the government of Theresa May, foreign secretary Boris Johnson. Critics of Johnson fault him for new charges being brought by Tehran against Nazanin Zaghari-Ratcliffe, a British and Iranian citizen arrested last year on trumped-up national security charges.