President Trump has long admired Richard Nixon, despite the Watergate scandal and subsequent resignation. Now this admiration has taken on a new dimension - threatening to "wipe out Iran as a civilization" before backing down when Tehran agreed to open the Strait of Hormuz.

This approach mirrors Nixon's "madman theory" in diplomacy - a concept where the adversary is convinced you are unpredictable and prepared to do anything to achieve your goals, thereby forcing them to make concessions they would not otherwise accept.

During a walk with future chief of staff Bob Haldeman in 1968, Nixon articulated this strategy: "I call it the madman theory, Bob. I want North Vietnam to believe I've reached the point where I might do anything to stop the war." He later instructed aides to convey to Soviet representatives that their leader was "a bit unstable."

Critics point out that Nixon's strategy in Vietnam resulted in the devastating bombing of Hanoi at Christmas 1972, and the peace terms were nearly identical to those before the bombing. A similar parallel is drawn now - Tehran agreed to open Hormuz but charges 2 million dollars per ship, meaning it profits more financially than ever before.

"Having not achieved a clear success in this conflict, he probably needs a significant move that would allow him to withdraw and declare victory," assesses Ali Vaez, director of the Iran program at the International Crisis Group. The question is: how many times can such tactics extract you from self-created problems?