One nuke in one container ship in each port would fatally cripple the US ability to respond to anything. China is more interested in scooping up Asian territory....and keeping the US out of the way.
I still could see a THE BEAR AND THE DRAGON scenario where China attacks Russia and we send the Rooskies aid via NATO....
There's 360 commercial ports in the US, according to American Association of Port Authorities. Canada has 18 major points, according to Association of Canadian Port Authorities. Mexico has 41 according to Coordinación General de Puertos y Mercante. So, that's 409 needed nuclear weapons. And that wouldn't necessarily take out our oil, coal and gas terminals that might be used for emergency port facilities. Or dry docks and repair yards. Oh, and Navy ports. Let's low-ball and say 500 nukes.
Most serious people put China's nuclear arsenal at 450-600 warheads on the top end, with a more realistic number at 300 ish. That includes warheads for 50-75 ish ICBMs. Going nuts and rounding up to a hundred, if China used every nuke not assigned to an ICBM (stripping their short range ballistic missiles) and nuked every port, they maybe could have enough nukes. Having 500 nuclear weapons delivered with no leaks or security violations, with perfect timing and placement, would be quite an achievement. That would literally last possibly an hour until we retaliated with at least twice as many nuclear weapons.
I hope it's popular here to bash Obama, but there's zero chance that we would not retaliate with nuclear weapons to such an attack. Not "one in a billion" we would fail to attack, absolutely zero.
And also make absolutely no sense. France pre-emptively nuking the hell out of Wisconsin and California is significantly more likely attack scenario with the current geopolitical climate. A unified French-British coalition could pull it off, and is just as likely/motivated to do so. Could the PRC govt be overthrown and get a new govt that is off the rails? Sure. But at the moment, it's as likely as the US successfully invading and occupying China.
I am legitimately curious. Why are any of y'all thinking this is remotely plausible with the existing governments?