But the Pentagon report describes something far more sophisticated: a China that has now leapt into the first ranks of offensive cybertechnologies. It is investing in electronic warfare capabilities in an effort to blind American satellites and other space assets, and hopes to use electronic and traditional weapons systems to gradually push the United States military presence into the mid-Pacific nearly 2,000 miles from China’s coast.

The report argues that China’s first aircraft carrier, the Liaoning, commissioned last September, is the first of several carriers the country plans to deploy over the next 15 years. It said the carrier would not reach “operational effectiveness” for three or four years, but is already set to operate in the East and South China Seas, the site of China’s territorial disputes with several neighbors, including Japan, Indonesia, the Philippines and Vietnam. The report notes a new carrier base under construction in Yuchi.

The report also detailed China’s progress in developing its stealth aircraft, first tested in January 2011.

Three months ago the Obama administration would not officially confirm reports in The New York Times, based in large part on a detailed study by the computer security firm Mandiant, that identified P.L.A. Unit 61398 near Shanghai as the likely source of many of the biggest thefts of data from American companies and some government institutions.

Until Monday, the strongest critique of China had come from Thomas E. Donilon, the president’s national security adviser, who said in a speech at the Asia Society in March that American companies were increasingly concerned about “cyberintrusions emanating from China on an unprecedented scale,” and that “the international community cannot tolerate such activity from any country.” He stopped short of blaming the Chinese government for the espionage.

But government officials said the overall issue of cyberintrusions would move to the center of the United States-China relationship, and it was raised on recent trips to Beijing by Treasury Secretary Jacob J. Lew and the chairman of the Joint Chiefs of Staff, Gen. Martin E. Dempsey.

To bolster its case, the report argues that cyberweapons have become integral to Chinese military strategy. It cites two major public works of military doctrine, “Science of Strategy” and “Science of Campaigns,” saying they identify “information warfare (I.W.) as integral to achieving information superiority and an effective means for countering a stronger foe.” But it notes that neither document “identifies the specific criteria for employing a computer network attack against an adversary,” though they “advocate developing capabilities to compete in this medium.”