Can you find the Pacific Ocean on a map and figure out where the open part would be and why the US said ""Don't think of trying something". They aren't talking about the area on your map close to shore nor the area near Taiwan. China has already done that. But they haven't done this with their carrier:
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This is the realm of the US Navy...not some Sea off of China. With two US carriers docked China may want to take a long trip...if her engines can handle it. What a better way to say we have a true blue water Navy (and reliably built) than by taking a full Pacific tour with a carrier. What a bold statement that would make.
But you are simply not comprehending what the US is talking about.
Now does China really have any balls after the warning...probably not.