So the biggest reason for the enormous raise in cost/hull has been the fact that the Navy did not have a solid non-changing plan before they finished the two hulls. So that means the navy has to come up with a concrete design which is large enough to be high endurance for a small crew, have more than one screw, can handle two V-22s/MH-60s, have ASW/AAW/ASuW/AMineW, small inflatable boat launch capability, can take a good sized hit, and can possibly support smaller attached PCs.
Can a ship under 4500 ton displacement, have a 155mm artillery gun (like that on the
Crusader or
FCS-NLOS),
SeaRAM/
VLS,
CIWS, Mounted Sonar systems, a boat launch ramp and docking stations for ships that are about
100-
300 tons, and can maintain
33 knots.