For Trump, the risks in Iran are significant. Although he is unlikely to commit ground troops, even a daring strike on the Fordo complex could be met with surprises. The U.S. certainly has the military edge, especially with the damage already sustained by Iran to its missile launchers. But as Carter found out, the best laid plans can go awry.

Donald Trump has made his most explicit comments yet about possible US military action against Iran, saying: “ I may do it. I may not do it .” The president also said next week or “maybe less than a week” would be “very big”,