North Korea's nuclear test this week has deeply angered China, a mood shift signaled in statements showing that influential Chinese thinkers are coming to see Kim Jong Il's regime as a liability.

The change in attitude doesn't indicate China will support punishment that could threaten the stability of its neighbor. China appears ready to support modest sanctions at the United Nations Security Council, along the lines of the restrictions on North Korean companies it has supported in the past.

But commentators from China have been stinging in their criticism since Monday's test. "North Korea has become a major problem for China," says Zhang Yushan, who works for a government think tank in Jilin province, near the North Korean border. "It has become a dangerous player in the world."

It is impossible for outsiders to gauge how such statements reflect the views of those setting Beijing's foreign policy. Still, signs of Chinese anger over North Korea's nuclear test are raising hopes in the Obama administration that Beijing will eventually take stronger action to restrain Kim Jong Il's increasingly confrontational regime.

Defense Secretary Robert M. Gates said he believes China was surprised by the North's nuclear test, which made it more likely Beijing will cooperate with U.S.-led efforts to clamp down on the regime in Pyongyang.