Beijing wants foreign vessels to give notice before entering "Chinese territorial waters," providing maritime authorities with detailed information -- including the ship's name, call sign, current position, next port of call and estimated time of arrival. It may sound like a reasonable enough request, especially if the ship is carrying hazardous goods, that is until you consider what constitutes "Chinese territorial waters."
Beijing asserts sovereignty over vast swathes of the South China Sea, under its widely contested and far-reaching nine-dash line, as well as disputed islands in the East China Sea.
Begging the question, will China try to enforce the new law in disputed seas? If it does, Pacific powers like Japan and the United States almost certainly won't comply. And in such a scenario, the question quickly becomes, how will China react?