UNHAPPY IRAN. Unhappy people, caught among rival factions of politicians bent on murdering each other while the government of the country dissolves into chaos. In its three millennia of history, Iran has never succeeded in developing a political tradition that depends on anything nobler than simple coercion. There has occasionally seemed to be progress toward stability, but it has always been followed, tragically, by periods of retrogression like the present one.

The uneasy truce between the secular radicals and the clerical zealots collapsed in June when the clergy hounded the then president, Mr. Bani-Sadr, out of office and out of the country. The first response, a few days later, was a bombing that killed some 70 people including the cleric who was then the second most powerful political figure in Iran. Over the summer, the government--using the term loosely, to indicate the clerical party now more or less in power--has executed some 600 of its political enemies. The other side--or perhaps, more accurately, the other sides, since identifications are far from exact--have responded with a series of assassinations of which the Sunday bombing is only the most spectacular. With one blast someone managed to dispatch both the country's current president, in office for two months, and its prime minister, in office for one month. From his exile in Paris, Mr. Bani-Sadr called it a "great victory."

Meanwhile, much of the economy is in a state of paralysis, and unemployment has reached levels at which the numbers become meaningless. But there have also been a couple of surprises. The army held together much more effectively than you might have expected under the Iraqi attack, which has now been at a standstill since early last winter. The army still exists. Further, the oil industry still seems to be operating steadily. Production is only a fraction of the rates of several years ago, but it's enough to earn a significant amount of foreign exchange. If it continues to hold up, and if the earnings aren't all spent for weapons, it may suffice to keep the country from starving. But if things are better than they might be, it also means that they can get worse.

The great threat confronting Iran now is open civil war. There are plenty of weapons in the country that aren't currently being used and, in the oil fields, there is great wealth to fight for. Civil war is the classic concomitant of revolution, and perhaps there are Americans heedless enough to say that it serves the Iranians right. But, unfortunately, it's not only the Iranians who have a stake in Iran. They are too close to the Soviets for that, and much too close to other oil fields crucial to every industrial economy in the world including, worse luck, this country's. There won't be excessive mourning here for the politicians who died Sunday. But sensible people will recognize that the bombing made Tehran more dangerous than ever, and the dangers are not confined to the borders of that one afflicted country.