Behind Ayatollah Ruhollah Khomeini's now outspoken concern about his revolution in Iran lies almost certainly a growing fear of an all-out showdown between the forces of religion and of the left.
"Never," he said last week, "have I so much feared seeing the Islamic Revolution end in failure."
It was the first time since he returned from exile 16 months ago that the Ayatollah had ever admitted openly the possibility of defeat.
The immediate objects of his chiding were the quarreling groups that enjoy his patronage -- particularly the Islamic fundamentalists led by Ayatollah Muhammad Beheshti and the less zealous lay group that includes President Abolhassan Bani-Sadr and Foreign Minister Sadeq Ghotbzadeh.
The sharp edge of Ayatollah Khomeini's remarks specifically against Ayatollah Beheshti, rather than against the Bani-Sadr group. Indeed, his aim at the moment seems to be to save Mr. Bani-Sadr from the steamroller represented by the combined fundamentalist forces of Ayatollah Beheshti's Islamic Republican Party, the Pasdaran or Revolutionary Guards, and the street mob of the Hizbollahi or "Party of God."
The current issue of the London Economist sees it as a struggle between "Iran's suit-wearing brigade" and the turbans of the fundamentalist mullahs (Muslim teachers). Ayatollah Khomeini probably knows that if he cannot keep these two groups together under his revolutionary umbrella, the way might be open for the umbrella to be seized by the left.
Within this left, waiting in the wings with guns, there also are two main groups. They are the avowedly Marxist Fedayeen-e Khalq (People's Fighters) and the Islamic leftist Mujahideen-e Khalq (People's Holy Warriors).
A vivid reminder of the presence of these leftists came June 12 when a rally staged by the Mujahideen in a stadium not far from the United States Embassy compound was shaken by violence. The Muslim leftists attending the rally were apparently attacked by right-wing Muslim fundamentalists or their street mob supporters, the Hizbollahi.
One of the main claims of both the Fedayeen and the Mujahideen to revolutionary legitimacy -- and to a say in shaping the new Iran -- is that their armed urban guerrillas bore the brunt of the struggle against the Shah during the 1970s.
For most of that decade, the clergy were lying low and Ayatollah Khomeini was physically safe in exile. Also in exile were Mr. Bani-Sadr and Mr. Ghotbzadeh. Ayatollah Beheshti, similarly, was in Europe for much of the time as religious adviser to Iranian students in West Germany.
Yet for all the battle scars gained during their fight against the Shah, the Fedayeen and the Mujahideen have been excluded and anathematized by Ayatollah Khomeini.
These two leftist groups briefly asserted themselves in April in demonstrations on university campuses protesting measures interpreted as directed against them and their activities. They were the targets then of fundamentalist violence, as were the Mujahideen again last week.
On this most recent occasion, Mujahideen leader Massoud Rajavi met the violence with the cry: "The struggle will last until victory, whatever the numbers of our martyrs may be."
But the leftists are divided just as are the forces under the Khomeini umbrella. To begin with, it is hard for the Mujahideen and the Fedayeen to cooperate in anything more deep than a tactical alliance. The Mujahideen profess continued commitment to Shia Islam. The Fedayeen are unashamed atheists.
Debate within the left is taking place at two levels. The first concerns the proper attitude toward the present revolutionary government in Iran. The second is about the correct attitude toward the superpowers.
In arguments about the superpowers, as reflected in exchanges among Iranian writers and intellectuals, the main question asked is: "Who is Iran's supreme enemy?" And the responses come in two ensuing and conflicting questions:
1. "Is it the US?"
2. "Should the China view be taken, which would make the Soviet Union the main enemy?"
As for discussion about attitudes toward the existing government, there are three apparent currents, each clearly identifiable at least within the Fedayeen.
One current says unreservedly that the present government should be overthrown and gives top priority to just that. A second says the present government should be supported ideologically, on the grounds that any manifestly "anti-imperialist" group merits backing. A third hews to the line of the old-time communist party of Iran, the Tudeh Party, which accepts the discipline of Moscow.
At the moment, the Tudeh Party is almost obsequious in its attitude toward ayatollah khomeini. This tactic is perhaps dictated by the scorn it has earned in the past because of its identification with the Kremlin line.
Ayatollah Khomeini certainly has no love for the Kremlin. But he has shown a certain tolerance for the Tudeh Party as such -- perhaps because it is for the moment challenging fundamentalism less openly than either the Fedayeen or the Mujahideen and is numerically less significant than they.
The Aytollah's prime aim clearly is to hold things together to prevent the revolution from "going down into nothingness" -- to use his own dire phrase of last week.