© Guang Niu/Getty ImagesA smoggy day in Beijing, where American air-quality monitoring once caused diplomatic difficulties.
This capital city's skies were clogged with pollution, as is often the case, and China's government was concerned. So it summoned officials of the American Embassy here to a meeting.
But the session had nothing to do with hazy skies. Rather, Chinese officials were peeved that the Americans were monitoring pollution themselves, and posting on Twitter for anyone to read, their more precise findings, which usually judged the smog far worse than official Chinese readings.
Chinese officials feared the conflicting information "might lead to 'social consequences,' " an American Embassy cable quoted the officials as saying. So could the Americans please block Chinese citizens from visiting the Web site?
That July 2009 cable, posted on the WikiLeaks Web site on Friday, is one of hundreds from the American Embassy in Beijing that offer a glimpse into the depths, and heights, of relations between the United States and Chinese governments. The cables, involving secret but not very diplomatically delicate correspondence between the two powers, cover topics ranging from China's claims on the South China Sea to the daily exercise regimen that the Chongqing Communist Party secretary, Bo Xilai, designed for himself.