Infighting in Iran may explain Higgins threat. Iranian disputes being played out in Lebanon

The threat to execute Marine Lt. Col. William Higgins, an American hostage, comes as domestic political battles in Iran appear to be stalling progress toward freeing American hostages in Lebanon. United States officials say they do not know exactly why the Lebanese hostage holders issued the execution threat at this time. But a number of them suspect it could be in part a spillover from leadership disagreements in Iran about how to deal with the US, as well as from tensions between elements in the pro-Iranian Hizbullah in Lebanon and more moderate Iranian leaders.

The ongoing power struggle among Iran's leadership has not abated since the cease-fire with Iraq, US specialists say.

At the heart of current debates, they say, is what kind of relations Iran should now have with Western countries, including the US. This makes Iran's approach to the hostage question a tempting area for Iranian radicals to block any broader rapprochement.

``I suspect,'' says an Israeli expert on Hizbullah and terrorism, ``the new threat is either connected to Iranian infighting, with more extremist elements in Iran urging the hostage holders to do more. Or the hostage holders themselves may be afraid Iran will not be firm enough and fear they may lose control of the hostages if they don't act and frighten the Americans.''

The US is concerned over the threat, but doesn't want to overplay it. Officials suspect the hostage holders are focusing on Colonel Higgins because they think he is the hostage who's most important to the US.

The statement about Higgins comes shortly after a positive Iranian signal on the hostages, US officials say. Last week in Beirut, an Iranian deputy foreign minister connected with the relatively moderate leadership factions said that Iran would continue to work for the release of Western hostages, even if four Iranians missing in Lebanon since 1982 turned out to be dead. He added that ``we refuse to allow any threat against the lives of innocents.''

A senior US official called this ``by far the most optimistic sign in the last six weeks.'' But some in Washington now suspect that the threat to execute Higgins may be a direct rebuff to that statement.

The US is working closely with United Nations Secretary-General Javier P'erez de Cu'ellar to mobilize international pressure against killing Higgins. Mr. P'erez de Cu'ellar has repeatedly called for the release of Higgins, who was working for the UN observer mission in Lebanon when he was kidnapped last February.

Sources contacted are not sure whether Higgins is alive or not.

The hostage holders' statement said that Higgins will be executed in retribution for last week's Israeli raid against the base of a pro-Syrian Palestinian group in Lebanon. While Hizbullah may hope to forestall further Israeli attacks, US specialists say, the raid is also a convenient way to put the hostage issue in the spotlight.

US specialists admit they have a weak grasp on machinations inside Iran. But reports of mounting executions in Iran, sociel turmoil, and continued policy fights among the leadership suggest that top-level maneuvering is intense.

US officials suspect that these convulsions had put the release of US hostages on hold, as Iran's leadership grappled with more pressing policy differences.

In the wake of the Iran-Iraq cease-fire, US officials say, it seemed that Iran's leadership saw clearly the need to address the hostage issue. The US has continued to argue that Iran must use its influence to free the US hostages in Lebanon as a first step toward improving bilateral relations.

In September and October, Washington received a range of signals that Tehran would show its good faith on the hostages after the elections. But nothing happened.

US officials speculate that Iranian radicals who oppose moving toward the US are fighting any improvement in relations by arguing that Tehran should not press its Lebanese allies for a hostage release. These radical elements have their own channels to Hizbullah, they add. In fact, Iran's Revolutionary Guards - on the left in Iran's political debates - are believed to have had ``a particularily strong interest'' in Higgins all along, one US specialist says.

Simultaneously, some in Hizbullah are souring on the direction of mainline Iranian policy. Reports from Lebanon suggest that a number of Hizbullah leaders are chafing at Iranian efforts to broker an end to fighting around Beirut between Hizbullah and the pro-Syrian Amal Shiites. Some Hizbullah leaders also reportedly resent pressure for them to work more closely with Syria.

Western hostages in Lebanon

1985* Terry Anderson (American) Thomas Sutherland (American) Alberto Molinari (Italian)

1986 Brian Keenan (Irish) John Patrick McCarthy (British) Frank Herbert Reed (American) Joseph James Cicippio (American) Edward Austin Tracy (American)

1987 Terry Waite (British) Robert Polhill (American) Alann Steen (American) Jesse Turner (American)

1988 William Higgins (American) Jan Cools (Belgian) Peter Winkler (Swiss)

*Year they were kidnapped