WASHINGTON — BY voting 55 to 44 to attach conditions to renewal of China's most-favored-nation trading status with the United States, the Senate has sent a signal to Beijing.The question, though, is how the signal is read: Do the Chinese see the vote as a warning that a majority of US lawmakers are willing to threaten China's trade status over its human rights, trade, and weapons policies? Or do they not worry, knowing that President Bush plans to veto the legislation and that the vote fell even farther short of the two-thirds majority needed for a veto override than expected? After the Tuesday night vote, Senate leaders of opposing views converged in warning Beijing that, despite the outcome, all members agree that China must change its policies. "I don't believe the Chinese leadership should take any great satisfaction because it appears now that the veto will be sustained," said Senate minority leader Robert Dole (R) of Kansas after the Senate vote. "There might be a clear understanding in the People's Republic of China if a bipartisan group of United States senators went to Beijing, met with the leadership, and spelled out some of the concerns we have," Senator Dole continued in his post-vote summation. "They're real; they're not going to disappear." The bill's sponsor, Senate majority leader George Mitchell (D) of Maine, has said he will continue to push for an override of Bush's expected veto. During the day and a half of floor debate, senators denounced China's human-rights record, its flourishing arms sales to the third world - including alleged sales to Syria and Pakistan of missiles capable of carrying nuclear warheads - and growing evidence of unfair trade practices. The debate centered on what is the most appropriate method of forcing China to reform. Bush administration policy has been not to use the most-favored-nation (MFN) status as the vehicle for change, but rather other pressure points more directly related to key issues. THE administration would, for example, handle arms sales in bilateral negotiations on missile control regimes. China's human-rights problem, still a thorn in bilateral relations, would stay in the purview of the State Department. The White House would combat unfair trade practices with retaliatory measures that pinpoint the particular infractions, not with the blunt instrument of attaching conditions to MFN. Opponents of the Mitchell bill worry that adding conditions to China's MFN status, which guarantees the lowest possible tariffs on Chinese goods entering the US, would cause China to import more from Europe and Japan, hurting in particular US agricultural exports. China currently does more business with the US than with any other country. "Elimination of MFN would make the human-rights situation worse," says Harry Harding, a China scholar at the Brookings Institution. "It would provide a pretext for tightening of political controls and a cutback of exchanges with the US." "The bottom line is that the US does not have much leverage in the country," says Dr. Harding. Supporters of the Mitchell bill argue that the US does not appear to have leverage in China only because it has never tried to exercise it. Some hold up the US's withholding of trade preferences to the Soviet Union as a factor in that country's decision to allow greater personal freedom. Others, including Sen. Lloyd Bentson (D) of Texas, cite past threats to MFN for human-rights concessions the Chinese have made. Conditions for renewal of MFN in 1992 put forth in the Mitchell bill include: an accounting of citizens detained in the pro-democracy movement; release of citizens imprisoned for involvement in the Tiananmen Square protests; end to exports to US of products made by prisoners; a halt to arms supplies to the Cambodia's Khmer Rouge guerrillas; adherence to the agreement for transfer of Hong Kong to Chinese rule in 1997. Opponents of these conditions say that, ironically, conditions meant to help Hong Kong's transfer would likely end up hurting it, because the disruption of the Chinese economy caused by a rupture in US-Chinese trade relations would damage Hong Kong's economy as well. As debate of the Mitchell bill proceeded, additional conditions were added, such as one requiring the administration to certify that China is not forcing abortion or sterilization on its citizens. Perhaps the most salient aspect of Congress's go-around on China and MFN is that it has forced the Bush administration to lay out its policy toward China, says Harding at Brookings. The Hill debate "reflects enormous American disappointment in China," says Harding. "It also reflects anger at the Bush administration for being so late in explaining what it is doing in China." Last week, in a letter to senators leery of the Mitchell bill but concerned about Bush's policy, the president outlined steps his administration will take to address the concerns over human rights, trade, and weapons proliferation. Bush promised tough sanctions for China's trade infractions and pledged to support Taiwan's entry into the international treaty government global trade. Mitchell complained the letter did not promise new action on human rights.