Thirty years ago, when I first studied language in Tehran, my class was a bit bizarre, with students from both Muammar Gaddafi’s Libya and Kim Jong-il’s North Korea. The North Koreans were in Iran for a purpose. Across the city, North Koreans would shuttle around in minibuses with their window shades drawn. I never found out what exactly they were doing.

When President George W. Bush coined the term “Axis of Evil” in his first State of the Union address following the Sept. 11 al Qaeda attacks on New York and Washington, D.C., critics pilloried him for lumping the Islamic Republic of Iran, Saddam Hussein’s Iraq, and North Korea together and suggesting coordination and interplay between them. They might have been correct regarding Hussein and Iranian Supreme Leader Ali Khamenei — though Iraq’s Republican Guards and Khamenei’s Islamic Revolutionary Guard Corps would cooperate on smuggling — but the relationship between Tehran and Pyongyang runs deep.