Vice President Mike Pence wants America to boldly go where man has gone before: the moon, and fast. He announced Tuesday that NASA has five years to put humans back on the lunar surface “by any means necessary.” If the agency cannot do that, he said, it is NASA that will have to change — not the mission.

The hurry with which the Trump administration seems determined to carry out so ambitious an aim makes clear that the primary goal is to advance not science but the image of U.S. dominance.

China landed a spacecraft on the moon’s far side this year. An Israeli craft is in orbit and scheduled to land soon, and India plans to follow. The U.S. blasted off in the 1960s not only because it was difficult but also because officials wanted to show we could do something hard more quickly than our adversaries. Now, the nation is eager to prove itself again.

Is the administration prepared to back its bluster with cash? NASA has a limited budget, and President Donald Trump’s requests to Congress suggest funding will become scarcer still. Another trip to the lunar surface would cost an estimated $100 billion or more. Keeping astronauts there for extended periods of time would be even pricier.

Robotic probes, on the other hand, can provide answers to compelling scientific questions on the comparative cheap. The Opportunity rover to Mars survived on the red planet for 15 years and cost only $800 million.