The University of Maryland has issued the results of a new national poll indicating that the American people overwhelmingly oppose putting weapons in space, so long as no other country deploys such weapons.

Where did that come from?

Actually, the United States has been talking about space weapons for decades. Consider this bureaucratese from the U.S. Air Force Space Command’s Strategic Master Plan FY06 and Beyond: “Non-nuclear prompt global strike from and through space can transform the war fighter’s role in the future. Most notably, a non-nuclear strike capability, possibly in the form of a Common Aero Vehicle (CAV) launched by a ballistic missile, air launch system, or a SOV [Space Operations Vehicle], could provide the President and the Secretary of Defense with a range of space power options. These options are for deterrence and flexible response when time is absolutely critical, risks associated with other options are too high, or when no other courses of action are available.”

Translation: Space weapons could give the United States the upper hand in some future national security emergency.

Such arguments have been repeated in dozens of public documents and think-tank reports in recent years. We’re not talking about missile defense, which has been debated for more than three decades. We’re talking about ground-, sea-, air- and even space-based weapons that could destroy the satellites of other nations. We’re talking about space-based weapons that, in theory, could pulverize earthly targets. And we’re talking about “space power options” that—in Pentagon-ese—could give the United States “full spectrum dominance” in space.

To be sure, space dominance has not been adopted as U.S. policy. But we are quietly edging toward it. And make no mistake: Such a policy would be regarded by other nations as an unacceptable violation of global norms—and a threat to their sovereignty.

“He who controls space controls the Earth” is an assertion that began popping up after the Soviet Union launched Sputnik I in 1957. The assertion is widely believed.

What would America do if we thought another country were about to place weapons in space? What would we do if China starts building advanced anti-satellite (ASAT) weapons that could bring the international economy to a halt by crippling global communications and navigation systems? What would we do if Russia announced plans to build tiny unmanned space bombers capable of striking earthly targets? What would we do if the country in question actually had the technical and financial resources to pull it off?

We would condemn such plans and call on the international community to impose draconian economic and political sanctions until the policy was reversed. One can almost hear a president telling the nation, “This violation of international law and custom, this threat to peace and freedom, this tyranny of the heavens, shall not stand.”

If efforts to stop the deployment of such weapons failed, the world would have a new space race. And military dominance of space, rather than peaceful space exploration, would be the goal.

Several nations, including China, have the potential to conduct limited military operations in space. But only the United States has the financial ability and technical wizardry to develop a comprehensive space-dominance system. We could—but we shouldn’t.

If the United States pursues such a policy, it would do so with the best of intentions. America would say that it would never deny access to space to another country, except under the most extreme circumstances. But what nation could afford to rely solely on the good judgment and benign intentions of another—in this case, the global “hyper power”?

Most of the nations with national security or commercial interests in space—whether those interests involve research, navigation, communication, exploration or observation—are on record as favoring a new treaty that would prevent an arms race in space. The United States opposes it.

Rather than explore our military options, the United States should denounce the “weaponization” of space and lead the treaty effort. A good question for the remaining presidential candidates: Will you fight for such a treaty, or risk a new arms race?