Maintaining aerospace leadership might require NASA, for example, to think even bolder about its dreams of flying to Mars and beyond.

"We have been fixated on the idea of the Kennedy message that took us to the Moon. So we have tended in our space program to say what's the next destination?" Walker said, noting the talk usually means going back to the Moon or on to Mars, with a space station thrown in for good measure.

"The question is whether or not that should be the focus of NASA and the focus of technological development -- or whether or not the focus should be larger than that?" he said.

A Mars mission has always been predicated on theories of making a rocket reliable enough to last the many months a round-trip would take, and in finding ways to keep the crew healthy, said Walker.

"That may not be the right way to develop technology," Walker said. "It may be that it's better to develop the technologies that will allow you to get to Mars not in a matter of months, but in a matter of weeks."

Talking about advanced propulsion -- and naming technologies including nuclear, "anti-matter and anti-gravity" -- Walker imagined routine manned spaceflights to Mars, exploratory missions to the rest of the solar system and robot probes landing on planets circling other stars within the next century.

Faster alternatives to rockets would be supported by Congress, he said.

"If you finally say to Congress 'Look, we have the technology that we can go to Mars and we can be there in a matter of weeks,' then I'd tell you there'd be some courage to do so," Walker said.

Charged with determining the best way to ensure that such things might be possible and that America's aerospace leadership continues, the commission's final report is expected to offer about a dozen recommendations and is due Nov. 19, Walker said.

Three interim reports have been released so far to offer suggestions on what might be done in the short term and to give everyone a general sense of the direction the commission is heading with its final recommendations, Walker said.

"Our whole goal here is to look out 25, 30 and 50 years into what we're going to do, and the issues here that arise are far more than technological issues," he said.

Walker chose the potential "Far East Space Race" between China and Japan as an example. Such a competition could rival the one between the United States and the Soviet Union during the 1960s. If China is successful with its efforts to launch a manned spacecraft -- perhaps as early as 2003 -- then Japan might respond with increases in its own program.

Such a race between those two nations, with their large real and potential economies, could leave America behind.

America already faces challenges to its airliner and commercial space launch industries from Europe, and soon the U.S. Global Positioning System could face stiff competition from the Galileo system proposed by Europe.

Among the keys to removing the threat: Re-thinking the way the government manages and finances its aerospace programs.

"The fact is NASA and the Defense Department are going to have to work together on some aerospace technology in the future," Walker said.

To make that happen, Congress will have to consider new ways of doing business, either restructuring the responsibilities of various committees or putting together some kind of overall aerospace board. However it's done, Walker said there's two criteria that must be met to ensure aerospace leadership.

"If what you do in aerospace doesn't end up either in meeting a national need or ending up with profitability, you're not going to get very far," Walker said.

The need for a new and better air traffic management system is a fine example, Walker said. The current system already is overly taxed and there are proposals out there for new services such as an "air taxi" that could add 20,000 to 30,000 new airplanes to the skies.

"And nobody believes the present air traffic control system can handle that volume of traffic," he said.

The solution might come in the form of an automated, space-based traffic control system that relies on surveillance, navigation and communications systems dedicated to air traffic control, all of which would have to be built, launched and operated.

"Now you are meeting a national need and creating profits for the industries involved," Walker said.