DEFENSE : NATO Turns to Task of Filling Woerner’s Shoes : There is no clear successor to the alliance’s late secretary general, who had transformed the post. Officials say an active, innovative leader is needed.

As senior ministers from NATO’s 16 member nations gather here today at a commemorative service for the alliance’s late secretary general, Manfred Woerner, they will start to address the crucial issue of succession.

Although Woerner, who died here Saturday, had been fighting a losing battle against cancer for more than two years, there has been little thought given to a successor.

In part, ambassadors to the North Atlantic Treaty Organization wanted to believe Woerner’s own conviction that he had defeated the disease and would resume his full schedule next month. And with no obvious candidate, such debate was avoided as potentially divisive.

For several reasons, the choice of a successor has never been more important to the future of NATO--America’s most successful and enduring military alliance:

* During his six years as secretary general, Woerner transformed the job from one dominated largely by thankless administrative tasks to one of genuine power. He laid out a new agenda for NATO in the post-Cold War era, then lobbied effectively to get the backing of member states.

* While Woerner was instrumental in defining NATO’s new direction--one that calls for changed relations with the former enemy nations of Central and Eastern Europe, a strengthening of the European role in alliance actions and a new job as a U.N.-endorsed peacekeeper--the alliance has taken only initial, tentative steps in all three areas.

“We’ve got a clear idea of what’s to be done, but it’s all just started,” an alliance diplomat said. “This is no time for a caretaker. We’ve got to keep moving forward.”

* With defense no longer the compelling issue it was during the four decades when a nuclear-laden Soviet Union threatened the West’s very existence, NATO governments today tend to be far less focused on alliance affairs--a fact that generates a power vacuum that can only be filled by an active, innovative secretary general.

Woerner used this new environment to develop and then effectively sell his agenda. If his successor fails to do the same, the alliance itself could flounder.

“Woerner made the job much bigger than it was,” said a senior NATO official here, who declined to be identified by name or nationality. “Whether this is sustained depends mainly on who takes over.”

The real search for a successor is expected to get under way next week after Woerner is laid to rest following a private ceremony in his home region of southwestern Germany.

At present, more than a dozen names float through informal chats at NATO headquarters, but doubt surrounds them all.

Those most frequently mentioned include former Norwegian Foreign Minister Thorvald Stoltenberg, who is currently attempting to mediate the war in the former Yugoslav federation; former Dutch Prime Minister Ruud Lubbers; the European Union External Affairs Commissioner Hans van den Broek, and former Italian Prime Minister Giuliano Amato.

“The right choice has to be a convinced Atlanticist, have a good feel for the needs of Eastern Europe and be close to the European Union’s attempts to build a defense profile,” said Uwe Nehrlich, deputy director of a German defense think tank near Munich known as the Ebenhausen Institute. “None of these have all three.”

Belgian Foreign Minister Willy Claes; his British counterpart, Douglas Hurd; and former Danish Foreign Minister Uffe Ellemann-Jensen are also discussed, but their interest in the job is unclear.

Certainly, nationality will play a role. An American is ruled out because the United States already holds the alliance’s most senior military posts. Luxembourg and Iceland carry too little weight. The Turkish-Greek dispute over Cyprus would appear to rule out anyone from those two countries, and another German is highly unlikely to succeed Woerner.

NATO officials anticipate southern European nations may stake a claim to the job on grounds that only one of NATO’s seven secretaries general has come from south of the Alps (Italy’s Manlio Brosio, who served 1965-71), but this alone will not be enough, they insist.

“The job has become too important to go to someone just because he’s the right caste,” noted one official.

While opinions differ on candidates, there is unanimity on one issue: that a divisive debate resulting in a weak, ineffectual compromise choice must be avoided.

“The Woerner legacy is fragile,” summed up a senior NATO source. “We desperately need someone with the perseverance and drive to keep us on our way.”

In the Running

Ruud Lubbers, Former prime minister, the Netherlands

Hans van den Broek, External affairs commissioner, European Union

Giuliano Amato, Former prime minister, Italy

Thorvald Stoltenberg, Former foreign minister, Norway