If somebody would have told me five years ago that by 2012 it would be commonplace for countries to launch cyberattacks against each other, I would not have believed it. If somebody would have told me that a Western government would be using cybersabotage to attack the nuclear program of another government, I would have thought that's a Hollywood movie plot. Yet, that's exactly what's happening, for real.

Cyberattacks have several advantages over traditional espionage or sabotage. Cyber attacks are effective, cheap and deniable. This is why governments like them. In fact, if Obama administration officials would not have leaked the confirmation that the U.S. government (together with the Israelis) was behind Stuxnet, we probably would have never known for sure.

In that sense, it's a bit surprising that the U.S. government seems to have taken the credit � and the blame � for Stuxnet. Why did they do it? The most obvious answer seems to be that it's an election year and the voters like to see the president as taking on adversaries like Iran. But we don't really know.

The downside for owning up to cyberattacks is that other governments can now feel free to do the same. And the United States has the most to lose from attacks like these. No other country has so much of its economy linked to the online world.

Other governments are already on the move. The game is on, and I don't think there's anything we could do to stop it any more. International espionage has already gone digital. Any future real-world crisis will have cyberelements in play as well. So will any future war. The cyberarms race has now officially started. And nobody seems to know where it will take us.

By launching Stuxnet, American officials opened Pandora's box. They will most likely end up regretting this decision.

Mikko Hypponen

This column was originally published in the Room for Debate section of The New York Times. Be sure to read the two other opinions from Ralph Langner and James Lewis.