The guided-missile submarine USS Ohio is strutting its stuff in a joint training exercise with small craft borne US Marines near Okinawa, Japan sending a message to the Chicoms of the capability of US subs. The USS Ohio does not, currently, carry nukes, but rather a variety of regular high-explosive warheads via 154 Tomahawk cruise missiles and an array of anti-aircraft and anti-ship missiles, as well as torpedoes.
But the bigger point is not the exercise near Japan, but rather that the Ohio passed very close to Taiwan some days ago UNDETECTED by the Chicoms, who have invested heavily in an array of anti-sub measures. This is a clear message to the Chicoms to be very careful about messing with Taiwan.
Now, it is true the Chicoms do possess an array of sub-hunter subs, anti-sub helicopters, and some anti-sub missiles. But, their effectiveness is limited to the waters much closer to China's coast. A US Navy spokesman stated we are very much aware of the Chicoms' capability to attack subs closer to their home waters, but vessels like the USS Ohio, and our others of the "Triton Class," can strike targets well inside of China without getting close to Chicom waters.