Anyone have some good analysis on what happens if China stops buying U.S. debt? Bloomberg is reporting China to Boost Yuan Swaps, Payments on Dollar Concern:

China’s leaders, increasingly concerned about the nation’s $740 billion of U.S. Treasuries, are making it easier for trading partners and consumers to do business in yuan.

The People’s Bank of China has agreed to provide 650 billion yuan ($95 billion) to Argentina, Belarus, Hong Kong, Indonesia, Malaysia and South Korea through so-called currency- swaps. More such arrangements are being planned so importers can avoid paying for Chinese goods with dollars, the central bank said. In Hong Kong, which has pegged the currency to its U.S. counterpart since 1983, stores from Park’n Shop supermarkets to jewelers accept yuan.

Chinese officials are using the Group of 20 meeting, which begins today in London, to call for reducing the dollar’s role and the creation of a new global reserve currency. Premier Wen Jiabao has said he’s concerned that a weaker greenback will erode the value of China’s Treasuries as the U.S. tries to spend its way out of the longest recession since the 1930s.

“China has learned from this financial crisis that we must reduce reliance on the dollar and promote the yuan as a regional or international currency,” Zhang Ming, secretary general of the international finance research center at the Chinese Academy of Social Sciences said in a March 31 interview in Beijing. “We need to shield our economy from any more turmoil in the U.S.”

Later down in the article details China says this is a warning that the United States must protect China's assets....

Now how are those trade agreements working again?