Despite denials from Beijing, there seems little doubt that China’s computer hackers are engaged in an aggressive and increasingly threatening campaign of cyberespionage directed at a range of government and private systems in the United States, including the power grid and telecommunications networks.

The Obama administration had carefully avoided naming a specific culprit. Now it has. In the Pentagon’s annual report to Congress on China, the Chinese government and, in particular, the Chinese military are explicitly accused of mounting attacks on United States government computer systems and defense contractors in a systematic effort to steal intellectual property and gain strategic advantage.

The report adds urgency to talks expected to begin in July with the Chinese about cyberissues. It does not discuss America’s own considerable investment in disruptive computer capabilities. These, too, must be on the agenda.

China’s ambitions have been discussed on a background basis by senior officials and were the subject of an earlier report by the computer security firm Mandiant that was disclosed by The Times in February. The new report to Congress adds depth and detail. Its clear purpose is to increase pressure on China to rein in its hackers, who Mandiant has said, are largely run by Chinese Army officers or are contractors working for military commands.