I suspect China will not directly strike North American ports, in the understanding that Chinese mainland ports are not hit either. The potentiel to mine port entrances and perhaps 1-2 subs on a one way missions off the west coast will be the most we see close to our shores. To sustain fleet ops in a gruelling but drawn out fight, you will need mobile facilities to repair and restock the fleet. China will use everything from threats, diplomacy, sabotage to limit the use of near theatre ports to sustain the fleet. Their goal is not necessarily the destruction of the fleet, but the expenditures of munitions. If your escorts are required to expend all their surface to air missiles to ward off potential strikes and inbound munitions. Then they be forced to return home to reload, that will very quickly denude your fleet of AD assets, forcing it further offshore and limiting their abilty to protect Taiwan or other friendly countries.