I can't imagine with the satellite image and compute we have it would be difficult at all to know the real_time +- 30min location of any carrier by maybe the top 5-10 states, even at night.
Commercial satellites can get 30cm resolution images (military satellites can likely get even more high resolution).
The earth is vast, but once you pinpoint a carrier, a simple software loop should be able to track it for ever (those carrier do not move fast).
I cannot imagine this being remotely difficult for a state to have a constant pin on every large carriers sailing on earth. There even might be some civilian apps for that too.
But again, Strava and other connected + geolocation apps have been an issue for military personnel in general.
I can't imagine with the satellite image and compute we have it would be difficult at all to know the real_time +- 30min location of any carrier by maybe the top 5-10 states, even at night.