Why is this revelation so strategically and diplomatically important? A few reasons. First, it amounts to a sign of a Chinese realization that its interpretation of the UN Convention of the Law of the Sea is not in its long-term interests. That interpretation has been that freedom of navigation does not include the right to conduct surveillance in another country’s EEZ. Most countries, including the United States, consider such surveillance to be a peaceful activity allowed under the convention. (To be clear, all including America agree that peacetime intelligence-gathering within the 12 nautical mile limit of anyone else’s territorial waters is a big no-no.)

As China’s economic and strategic interests, and naval capabilities, extend ever further from its shores, it seems that some within the Chinese security establishment are anticipating future benefit from their own country having the legal right to gather intelligence in other countries’ EEZs. After all, if they had continued their old policy, perhaps a third of the world’s maritime space would have been barred to their operational activity, at least in legal terms.

But for now, if China is indeed conducting the occasional surveillance foray in America’s EEZ, then it is technically in breach of its own interpretation of sea law.

Moreover, if China is admitting that it is starting to compete with America at its own game, then this could be read as an acknowledgement that the U.S. Navy is not going to be persuaded to give up its surveillance in East Asian waters. Incidents like the harassment of the USNS Impeccable in 2009 were generally believed to have been part of a campaign to push the Americans back. It is fair to speculate that China now recognizes that that campaign has failed and that it needs to try a new tack.