The terrible message is precisely that NATO is only defensive in theory, but is willing to expand into the Pacific to defend a territory that is nowhere near its original purview.

The problem with the "purely defensive" argument is that historically, NATO Article 5 has been invoked to declare a war on a country that only indirectly threatened a NATO ally's regional stability. That's how NATO ended up bombing Serbia, which was doing despicable things to Albanians, but was not threatening NATO sovereignty to a degree that justifies Article 5.

Add these two together and China's opposition to a NATO presence in the Pacific makes a whole lot of sense.