“The stars will never be won by little minds,” observed the great science fiction writer Robert Heinlein. If we aren’t careful, though, they just might be won by the scheming minds of governments hostile to the United States.

A notable recent New York Times piece reported that the “Pentagon is rushing to expand its capacity to wage war in space, convinced that rapid advances by China and Russia in space-based operations pose a growing threat to U.S. troops and other military assets on the ground and American satellites in orbit.”

There are two things to be said about this — one, it’s about time, and two, we need to be doing much more.

Playing defense in space — or simply trying to protect our assets — doesn’t make any more sense than doing so on the ground, in the air or on the sea. Would we ever just give our troops lots of Kevlar vests and station them in elaborate concrete bunkers, but deny them the use of rifles or artillery?

Even if we wanted to keep space weapons-free, space is already a domain central to modern military operations. Try to operate a U.S. carrier strike group or even an infantry brigade without the communications, positioning information or reconnaissance provided by space. As the assistant secretary of defense for space has put it, space is “absolutely essential to our way of war.”

Russia and China realize that. Since they aren’t nice, well-meaning people content to see the U.S continue as the world’s foremost military power, they have set about finding ways to eliminate our advantages.

In response, we have been working on making our satellites harder to take out. We’ve been reducing our reliance on large, sophisticated satellites that are expensive to build, supposed to last for decades and are enticing targets. We’ve been adding higher numbers of smaller satellites. They are cheaper, aren’t built to last as long so they can evolve technologically more quickly, and can be launched much more rapidly. This will create a more resilient force.

But defense isn’t enough. We should arm our spacecraft with the non-kinetic (electronic and cyber warfare capabilities, together with directed energy) and kinetic weapons necessary to disable or shoot-down threatening satellites.

Space also should be used to intercept nuclear weapons. Merely holding out the possibility of a nuclear launch could be used to coerce the United States in a crisis and, much more seriously, a nuclear attack could deal American society a blow from which it will never recover.

It is insane that our chief means of protecting ourselves from this threat is several dozen decades-old ground-based interceptors. We should be pursuing capabilities, such as space-based lasers, that were once the stuff of science fiction. In a pinch, it’s hard to believe a U.S. president will ever regret having more ways to shoot down an incoming nuclear missile.

All this will require national focus, and a clear-eyed view of a contested domain critical to our ability to deter and win wars.

Rich Lowry is editor in chief of the National Review