L.A. Mayor James K. Hahn has put forward a serious, if rather bizarre, proposal for "renovating" instead of "expanding" Los Angeles International Airport.

His plan would ban cars from the central terminal area and force passengers coming and going to an off-site terminal for baggage check-in and pickup with a people-mover train carrying passengers to and from the airport.

By demolishing four terminals, building a new one and reconstructing the runways, the mayor says air safety would be dramatically improved and the off-site control of baggage would make LAX dramatically more secure at a time of great fear of terrorist attacks.

Finally, and just as importantly, Hahn says passenger traffic would be capped at 78 million passengers a year, about 25 percent more than currently use LAX, but far below the previous plan that was scuttled by broad opposition from throughout Southern California.

The Hahn plan begs a thousand questions that can only be answered by real leadership that brings together leaders from throughout Southern California and the airlines who create their own flight schedules and have never accepted voluntary caps on how much traffic they bring into an airport.

The critical issue is, Hahn's cap on LAX passengers is just a theory.

He hopes it will allow LAX to dominate the lucrative long-haul passenger market and leave short-haul flights to other airports, including Long Beach, Burbank, Ontario, Palmdale and John Wayne.

But that just won't happen by the magic of some invisible hand.

The mayor needs to initiate serious talks with officials of the 100 or so government entities that fought former Mayor Richard Riordan's massive expansion plan. He needs to get Orange County to accept its share of passenger traffic and to win support from the airports other than Ontario and Palmdale, which are owned by the city.

Congressional support from throughout Southern California also will be needed to get the federal funding necessary for "renovating" not just LAX but all regional facilities. A unified Southern California congressional delegation will bring the Federal Aviation Aviation aboard.

And that solid wall of this vast region pulling together, speaking with one voice on behalf of a comprehensive regional air traffic plan, is the one and only way that airlines will be made to cooperate.

Hahn has opened the door to a possible real solution that would affect the lives of the traveling public in all of Southern California. Now, he must step forward to provide the leadership to get the entire region to share in the burdens and opportunities.