From The New York Times:
China’s leaders introduced a bill on Tuesday that would effectively pre-authorize military action if Taiwan took concrete steps toward formal independence, a move American officials have said they fear could increase prospects for cross-strait conflict.
The legislation specifies that any changes in Taiwan’s Constitution seeking to legalize the island’s de facto independent status could be a trigger for military action. It is a direct challenge to President Chen Shui-bian of Taiwan, who had made changing the Constitution a paramount goal of his second term in office.
The bill, which is expected to be passed by the National People’s Congress next Monday, does not compel China’s leaders to initiate military action. It allocates powers to them that they have long been assumed to have and puts the leadership in a position to judge if and when Taiwan has ventured too far toward formal independence.