The Baha'i faith is a relatively obscure religion that sprouted 80 years ago in this country like a seed wind- blown from its native Iran. It has spread quietly to more than 7,400 places in the United States, and some 100,000 American followers. It has flowered, however slightly, in every nation of the world. But there is an ugly chapter being written in the history of the Baha'is. It is told in congressional testimony and in press releases from Baha'i national headquarters in Wilmette, Ill., which chronicle in grim detail the awful fate of the single largest concentration of the Baha'i faith -- the 300,000 or more followers in Iran. In the words of Firuz Kazenzadeh, a Yale history professor and secretary of the National Spiritual Assembly of the Baha'is in the United States, Iranian Baha'is face nothing less than "the threat of genocide" at the hands of Khomeini's Islamic fundamentalist government.

Khomeini's objective is clear enough. At hearings held by a House subcommittee this year, witnesses testified to the killing of 110 prominent Baha'i figures in Iran in the past three years; the jailing of hundreds and the "disappearance" of scores more; the destruction of homes, denial of jobs and pensions, firing of teachers, ousting of children from public schools, confiscation of property, sacking of holy shrines. In all this, Kazenzadeh and other American Baha'is see a systematic campaign of terror designed to force Iranian Baha'is to recant what is seen as their "heresy."

That has been the lot of the Baha'is, in some measure, since their break with many (but not all) Islamic beliefs nearly 150 years ago. During the "modernization" phase of the late shah's long reign, the Baha'is fared better. Though they were often harassed and even repressed by the shah, they were not massacred. Nowadays, scarcely a week passes without fresh reports of unimaginable brutalities directed against Iran's Baha'i leaders:

"A mob, after destroying the local Baha'i center, fell upon a man and his son, dragged their bodies through the street and chopped them up into little small pieces that were finally consigned to flames. . . . Fifteen masked men attacked a couple in their home at night, poured kerosene on the husband and set him on fire before forcing him to run for a few yards. Finally they heaped wood upon him, burning him to death. His wife, subjected to similar treatment, died a few days later."

The religion of the Baha'is is both benign and beneficent. It is stern about some things (alcohol, drugs, premarital sex), but liberal about religious dogma, and vigorously against discrimination or prejudice. It is dedicated to peace and world order, self-improvement and community service. In recent weeks, the American Baha'i community has prevailed upon the Senate to pass a resolution condemning the Iranian government's treatment of the Baha'is. A companion resolution, calling upon the U.S. government to avail itself of every opportunity to mobilize international condemnation is expected to pass the House. That's the least the U.S. government could be expected to do--but also, alas, the most it can do. U.S. influence with post-shah Iran is next to nil, and the ferocity and intensity of the fundamentalist assault on Iranian Baha'is does not augur well for even the most vigorous international effort to stop it.