The ministers are also expected to agree the military restructuring of the 19-member Alliance, whose transformation from Cold War bloc to global security force was accelerated by the September 11 terrorist attacks.

NATO wants to start to register the military and political lessons of the Iraq war, which sparked an unprecedented crisis within the 19-member organization, diplomats say.

One senior US official said NATO had undergone a "near-death experience" in February, when three anti-war countries blocked the Alliance from providing defensive support for Turkey ahead of the Iraq conflict.

"But we've healed an awful lot in a short time," said another diplomat, trumpeting accords for NATO to take command of peacekeepers in Afghanistan and to support Poland in setting up a stabilization force in Iraq.

Rumsfeld called Wednesday on US allies in Europe to unite, despite bruising differences over Iraq.

"It is really a matter of attitude, of the vision the countries bring to the transatlantic relationship and to the challenge we all face in the years ahead," he said.

Iraq is top of the agenda at the start of the meeting, when Rumsfeld and his British counterpart Geoff Hoon will brief their fellow ministers on the situation on the ground.

NATO agreed earlier this month to support Poland in establishing a multi-national "stabilization" force in Iraq, of which Warsaw -- a key European ally of Washington during the war -- is to command one sector.

The United States has made no secret of its wish for NATO to be even more involved.

The other key subject for discussion is NATO's military restructuring. The 19-member Alliance -- set to expand to 26 nations next year -- had already vowed to reorganize itself after the Cold War.

But September 11, 2001, accelerated that process, leading to a decision in May 2002 that NATO should go "out of area" - beyond its traditional European theatre of activities - and culminating in a landmark summit in Prague last November which was dubbed the alliance's "transformation summit."

To that end NATO is reorganizing its military structure, replacing the two current commands -- one in Europe, one in the US -- with a single operational commander based in Europe and a "transformation commander" based in the US.

The Brussels meeting is also expected to agree the "military concept" for a new NATO Response Force (NRF), comprising more than 20,000 crack troops ready to deploy in days worldwide.

Another item likely to fuel discussion in the corridors will be finding a successor to NATO head George Robertson, who steps down in December after four years at the helm of the world's premier military alliance.

According to one diplomat, the field has narrowed to two names -- Portugal's European Commissioner Antonio Vitorino and Norwegian Defense Minister Kristin Krohn Devold, who if successful would be the first woman in charge of NATO.

WAR.WIRE