These dysfunctional relationships have much in common.
Both have persisted far longer than rational self-interest would dictate. Our low-level war with Cuba has lasted 55 years, the one with Iran 35 years. No other countries in the world have been targets of our active enmity for so long.
A second similarity between these two long-lasting feuds is their deep historical roots. Cubans and Iranians nurture passionate nationalism that includes collective memory of traumatic American intervention. In 1898 the United States reneged on its promise to allow Cuban independence after the end of Spanish rule; 61 years later Fidel Castro referred to that betrayal in his first speech as leader of victorious rebels. In Iran, much resentment of the United States can be traced back to our role in deposing the country's last democratically elected leader, Mohammad Mossadegh, in 1953.