China does not want it's neighbors to have nuclear weapons, but now it is now facing several nearby countries that can, and are now indicating interest in, developing nukes. North Korea is the major troublemaker, and the Chinese are trying to get the North Koreans to back off their nuclear ambitions. South Korea and Japan threaten to go nuclear if North Korea does, and both countries could probably do so in a year. But most worrisome is Taiwan, which is now (again) discussing building nuclear weapons as a cheaper, and more certain, way to keep the Chinese out.