The U.S. is aggressively ramping up its ability to conduct offensive cyberwarfare, and successful operations have already been carried out, the New York Times reports.

Last week, the Wall Street Journal reported that President Obama was creating a new military command to gather all Pentagon cyberwar capabilities under one roof.

But the Times cites at least two cyberwarfare operations personally approved by President Bush while he was in office — one to penetrate computers used by Iran's nuclear program, with still-unclear results, and the other a successful attempt to lure members of Al Qaeda in Iraq into a military ambush.

A current project is much more ambitious — a working model of the entire Internet, one that can be repeatedly "war-gamed" to test for vulnerabilities.

The cyberwarfare capabilities of Russia and especially China worry both civilian and military officials.

The Times report cites a recent study that examined intrusive remote "scans" of computers controlling energy, financial and transportation infrastructures — and found that 90 percent of them came from China.

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