THE release of hostages John McCarthy and Edward Tracy makes it seem more likely than ever before that the long ordeal of Western captives in Lebanon will finally be brought to a close.Statements from the kidnap groups, from public figures in the radical Lebanese Shiite camp, and in the Iranian media all signal that a comprehensive process is under way that would involve freedom for Islamic militants held in Israeli jails and for Israeli servicemen captured in Lebanon, as well as for the Western hostages. But diplomats and analysts in Beirut caution that the very complexity of such a package and the diversity of the players involved could bring problems and delays. Observers point to many factors that indicate that the latest two releases portend a process, and are different from the piecemeal, haphazard way in which Western captives were freed in the past. Mr. McCarthy and Mr. Tracy not only are of different nationalities but were being held by different kidnap cells, the Islamic Jihad and the Revolutionary Justice Organization. Earlier releases have tended to involve one nationality at a time, reflecting that country's relationships with Iran and Syria or piecemeal deals over individual hostages. The same impression is reinforced by the new role being allotted to the United Nations by the kidnappers and their sponsors, who were clearly seeking a neutral vehicle for the process. The abduction of French aid worker Jme Leyraud within hours of John McCarthy's release last Thursday was clearly aimed at blocking further releases. But massive pressures exerted by Syrian and Lebanese security forces obliged Mr. Leyraud's captors to release him. It was the first time an abducted Westerner had been released in that way. There were signs that a similar process was starting to get under way in April last year, with the release of American hostages Robert Polhill and Frank Reed. But it was a false start, called off, Shiite radicals said, because the West failed to respond. Diplomats and analysts say that three elements have come together to produce the sea change that has made the releases possible: Iran's desire to improve relations with the outside world, Syria's wish to play a key role in the new regional order, and changing Syrian strategy in Lebanon. Diplomats give primacy to Iran's role, because of its uniquely close relationship with the Shiite radicals in Lebanon who are holding the hostages. They share the view that President Hashemi Rafsanjani has for some time been trying to rebuild cash-starved Iran's bridges with the West, but has faced problems and delays in doing so. Well-placed Iranian sources in Beirut have been signaling for some months that everything was clear for the release of hostages as far as Tehran was concerned. In June, the Tehran Times, close to President Rafsanjani's Foreign Ministry, predicted that releases were imminent. The subsequent delay was blamed on Israeli attacks in south Lebanon. The Tehran Times first predicted the release of a Briton and an American hostage. The abduction of Leyraud last Thursday was swiftly denounced by pro-Iranian Lebanese Shiite radicals. "We want to close this whole file," their spiritual mentor, Sheikh Muhammad Hussein Fadlullah told a prayer meeting the following day. "There are no benefits for anyone inside or outside Lebanon in returning to kidnapping." The Tehran Times newspaper saw Leyraud's abduction as an attempt to sabotage Iran's efforts to free the Western hostages. "Sincere efforts had been made to close the hostage file forever and a plan was launched so that all the hostages wherever they may be should be freed," it said. Syria, bidding to become a key player in the new, US-dominated regional order that emerged after the Gulf conflict, is seen by diplomats as having an equally strong interest in bringing about hostage releases, and its military presence in Lebanon makes it uniquely qualified to do so. Syria's incentive was made even stronger by its commitment to the strongly pro-Damascus government in Beirut, which has been taking big strides in reimposing state control in the capital and elsewhere. "The swift and decisive manner in which Leyraud was released certainly augments the credibility of the process which seems to be getting under way to free the hostages, and also gives a big boost to the Beirut government's prestige and the peace process in Lebanon itself," says a senior Western diplomat. Shiite sources say Leyraud was kidnapped by dissidents within the radical Shiite camp, disgruntled at the release of hostages while their comrades - possibly kinsmen - remained in Israeli and other jails. In their statement announcing Leyraud's release, his abductors - who called themselves the Organization for the Defense of Prisoners' Rights - said they had been given assurances that the hostage issue was being linked to that of the detained Islamic militants. Announcing the release of a US hostage on Sunday, the Revolutionary Justice Organization's statement spoke of a "positive, encouraging climate regarding continuing negotiations to settle the issue of our brothers detained in the world's prisons, especially Sheikh Abdul Kerim Obeid." Many other statements from Shiite radicals and from Iranian and Syrian officials point to a strong expectation that progress will follow in persuading the Israelis to give up Sheikh Obeid - abducted by Israeli commandos from his south Lebanon village - and other Shiite prisoners. Clearly, with the Israelis insisting that they must secure the return of their seven missing servicemen or their remains if they are to free Shiite prisoners, there is plenty of scope for hitches. "Even so, it's the first time that we've had any real hope that the whole sorry chapter of the hostages may be closed at last," says a diplomat in Beirut.