The AUS Joseph McCarthy was one of the older Statesmen class ships left in the Shen Zhou System to protect American Union interests in the system, specifically the system's SLE.
The ship was tending to a damaged freighter arriving in system when a long range attack from The Magnetic Assembly was launched against the SLE. While attempting to defend the SLE, its outer hull was damaged by drones hidden inside the freighter it was helping and then the ship itself was destroyed by a Radio-Wave-Laser strike from the AUS Azathoth's Wave.