Take the most combustible, scarred, dysfunctional relationship the United States has with any country in the world and place it in the hands of an impulsive, ignorant, bullying American leader and you are likely to sleepwalk to the brink of war. That is what just happened with President Trump and Iran. It was no surprise. He has been fiddling with this grenade since he took office.

By killing Maj. Gen. Qassim Suleimani, the commander of Iran’s elite security forces and the iron fist of the Islamic republic’s theocratic ideology, Trump tossed that grenade at the Middle East. It was a reckless act, like the president’s scrapping of the Iran nuclear deal. It united, for now, a divided Iran. It ensured that a half-century from now Suleimani’s name will be hurled at any American visitor to Tehran as evidence of the perennial perfidy of the United States.

The Iranian response, a ballistic-missile attack on military bases housing American troops in Iraq that killed nobody and did limited damage, was typical of a regime that has survived more than 40 years through prudence. The mullahs are not the “messianic apocalyptic cult” once evoked by Benjamin Netanyahu. They are cold calculators. Their primary objective is survival.

The response did just enough to appease popular anger and satisfy the supreme leader, Ayatollah Ali Khamenei, while avoiding provocation of the United States, a far superior military power and far more resilient body politic. The Islamic republic is in an untenable position. It is torn between a young majority that seeks normalized relations with the world, and the aging apparatchiks of the theocracy who depend on “Death to America” and confrontation. This is not a society ready for war.