Associate Editor for The Atlantic Matt Schiavenza outlines three reasons why China opposes a military strike against Syria, an Obama-backed decision which now awaits Congressional approval and which has already been heavily criticized by the Chinese. These reasons include resentment towards the UN resolution which led to fall of Muammar Gaddafi, general opposition to American intervention in foreign conflicts, and fear of a post-Assad future:
There's really no evidence that China has any special affection for Bashar al-Assad or views him as essential to Syria's future, but Assad is a known element, and China believes that his departure will be chaotic. Syria lacks a unified opposition, a shadow government, or any other institution that could step in should Assad's regime collapse, so a military endeavor that decapitates the government might just make everything a whole lot worse. Plus, Beijing fears that an Islamist movement in Syria may radicalize China's Uighur population, a Sunni Muslim group which occasionally clashes with the Communist Party government.What will China do if the U.S. strikes Syria—and how much would an attack damage Sino-American relations? Wuthnow says this depends on how Washington goes about it. If President Obama orders a ground invasion of Syria, China would have serious objections—but a brief round of airstrikes would cause a more muted reaction: “We'd see some rhetorical flourishes from the Ministry of Foreign Affairs or in the People's Daily condemning it, but China wouldn't let an airstrike damage their relations with the U.S.,” says Wuthnow. Not least because, given its still-modest military strength, China lacks the capacity to intervene even if it wanted to.Regardless of what happens, it's safe to say that China, by opposing any military strike, is on the side of the American public. Within the United States, support for invading Syria is infinitesimal, with many hawkish Republicans (even Donald Rumsfeld!) expressing misgivings. And over the years, Chinese warnings about the risks of American intervention have proven remarkably prescient: neither Iraq nor Libya have exactly turned into oases of stability since the overthrow of their strongmen. Whatever China's motivations for opposing an invasion of Syria, its non-interventionist instinct seems to have proven merit.[Source]
A BBC report sums up the negative Chinese media reaction to a potential US military strike:
Official media as well as experts from China's top think-tanks are warning against a possible US military strike on the Syrian government before a United Nations investigation into the possible use of chemical weapons is concluded.”The US' logic is that chemical weapons are in the hands of the Syrian army, so once these weapons are used, they can only be used by the government army. Amid a situation of turmoil and the chaos of war, this cannot be regarded as correct logic,” comments Qu Xing, director of the China Institute of International Studies, a foreign ministry-affiliated think-tank, in the People's Daily.”The US may fall into another protracted bloody war once again and its outcome may be even worse than the fate of [the] US military in Iraq and it may further accelerate the decline of America. We urge Obama to think twice before acting,” warns Liu Zhilin, a former Chinese diplomat, in the Global Times website.[Source]
And NBC News suggests that ordinary Chinese citizens, who have been instructed to leave Syria immediately, want to avoid war:
“Using chemical weapons on civilians is bad, but launching war will only make more ordinary people suffer,” said Guan Yongxing, 61, a retired Beijing taxi driver, adding, however, that “China should not get too involved in external conflicts, because it will only divert our resources from economic development which should be the priority.”The dominant anti-war opinion appears to provide domestic support for China's strategy to oppose unilateral military intervention, seek a negotiated political solution in Syria and direct the debate to the U.N. Security Council, where it has veto power. It has exercised such veto power twice to support the Assad regime.”I support peace and oppose war. We could punish Syria through economic sanctions,” said Li Yilin, 22, an accountant.[Source]
Read more about China-Syria relations via CDT.