Last October, the Justice Department uncovered what it said was an Iranian plot to assassinate the Saudi ambassador in Washington. There were many skeptics who claimed the Iranians were far too skillful and suave to have connived at such an amateurish plot involving a deadbeat Iranian expatriate in Texas and a Mexican drug cartel. Don’t the Iranians at least practice better tradecraft?

Apparently not, to judge by today’s explosions in Bangkok. A man suspected of being an Iranian agent tried to throw a hand grenade at pursuing police officers but instead blew his own legs off.

This Keystone Kops episode comes on top of yesterday’s attacks in New Delhi and Tblisi where suspected Iranian agents bungled the attempted assassination of the wife of an Israeli defense official and an embassy worker. The attack in New Delhi actually wounded the victim, but the bomb in Tblisi was found and defused.

On one level these events are comforting because they suggest that Iran and its proxies in Hezbollah are not as skillful as generally assumed. But on another level these events should be deeply discomfiting to anyone who subscribes to the notion that the Iranians are calculating Realpolitikers who act so cautiously they can even be trusted with the possession of nuclear weapons. Au contraire: The events of the last two days suggest the Iranian regime, assuming it is responsible for these attacks, is capable of acting in self-defeating, irrational but dangerous ways. In short, hardly the sort of people we should trust with a BB gun–much less nuclear weapons.