Now that the shuttle Discovery has landed safely, NASA is eager to get back on track. But the real decisions about the future of human space travel will be made elsewhere — at the Pentagon, and perhaps in other capitals, notably Beijing.

Looking ahead to more space exploration, NASA Administrator Michael Griffin said last week, "This is an important enterprise for America and the world — for humanity." The space chief might be right about that, but policy has never been based on such abstractions. Even during the golden age of space exuberance, in the '50s and '60s, the real motivation for exploration was distinctly terrestrial: getting the best of the Soviet Union, our rival during the Cold War decades.

In 1962, John F. Kennedy declared that it was America's goal not only to go to the moon, but also for the United States to become a "spacefaring" nation, in the way that, say, Britain was a seafaring nation.

And although Kennedy was caught up in the romance of discovery across what he called the "new ocean" of space, he was mindful, too, of more hard-nosed motivations.

Five years earlier, in 1957, the Soviets had been the first to launch a satellite into space, a feat that sent shock waves through America's sense of self. Were we the leaders in technology, or not? And could we defend against some hypothetical space weapon that the Russians might have up their sleeves? Also in 1957, the Gaither Commission produced a report concluding that the U.S. was lagging behind the Soviet Union on intercontinental ballistic nuclear missiles.

The so-called missile gap ultimately proved to be an illusion, but Kennedy's victory in the 1960 election was based in no small part on the idea that only JFK could "get the country moving again" — and that meant getting the country out in front of the U.S.S.R. Which is to say, for all the Captain Kirk-ish verbiage associated with the space program — "to boldly go where no man has gone before" — the twin great struts of support for NASA were international one-upmanship and military rivalry.

And, of course, once the United States mobilized, it quickly overtook the Soviets in the "space race." Indeed, even before Americans first landed on the moon in 1969, the Russians had given up. Whereupon the United States soon lost interest, too — the last American touched down on the moon in 1972.

But all along, the Pentagon continued its own drive into space, developing new missiles and anti-missiles, satellites and anti-satellites. So one might ask: Why can't the National Aeronautics and Space Administration continue to piggyback on the military's momentum? The answer is that NASA has traditionally seen itself as a showcase for manned — oops, make that piloted — space flight. And yet as aerospace technology has progressed, the need for human beings has regressed.

Put simply, many of the hot new tools that the military sends aloft — from Predator-type drones in the atmosphere to killer satellites in orbit — are effective precisely because they don't need air-breathing crews. In fact, NASA doesn't want to admit it, but even the shuttles, such as Discovery, could be operated without crew members.

So is there any hope for humans in space in the future? Or will everything be computers and robots? Most likely, plans to send humans back to the moon or on to Mars won't amount to much until an old inspiration becomes a new inspiration — that is, international rivalry.

Only this time, it won't be the Russians but rather the Chinese. Two years ago, China became only the third country to independently launch a human into orbit. Americans were too busy fighting in Iraq to pay much attention, but soon enough, it will become apparent that the Chinese are serious about space exploration, including colonization of the moon.

And at that point, when we realize that a new rival is beating us, we will get moving again and start competing to get our kind to the moon. But not until then.

James P. Pinkerton is a Newsday columnist.