The US are constantly playing war games, and conducting military exercises with foreign navies.
These are always taken very seriously, there is a great deal of professional pride at stake on all sides, if navy X can beat navy Y in some war
The results of these naval exercises are studied afterwards in minute detail, and used to improve tactics, (and technology), and provide realistic
simulated full combat experience for whole crews in peace time.
Now US carrier battle fleets at full combat readiness status, have more than once had a foreign submarine surface right along side a US carrier. Thus
demonstrating that small quiet electric boats CAN evade the most sophisticated antisubmarine detection the US has.
An Australian Oberon submarine once took a really close up photograph of the propellers of a US nuclear powered carrier that was at full battle alert
during a joint exercise.
The Chinese (cheeky buggers) have popped up beside a US carrier, during exercises more than once, even when they were not even supposed to be part of
the war game.
The idea that US carriers are totally 100% protected is nonsense.
If a nuclear torpedo sinks even one US carrier and takes a full crew of 6,000 Americans with it, that might turn around the US publics enthusiasm for