I know. However - if the Navy's core role is war fighting, surely it makes no sense to dilute war fighting capabilities in favour of constabulary tasks? I fear the politicians have been asleep at the wheel for years. More importantly - we need people!
Nope. Horses for courses. Once you get to a certain length of ship, monohulls overcome the advantages of trimarans and cost less. Triton was built to confirm the numerical modelling predictions for hydrodynamic performance and structural loading to verify the design tools to allow folk to come up with sensible designs. It wasn't a prototype or anything like that.
For the US one, they wanted a shedload of deck area at low weight/displacement for high-speed, hence aluminium trimaran. As FFG(X) gets bigger and assuming it doesn't have an unfortunate outbreak of go-faster stripes, a trimaran will be less attractive.
Back to OPVs and their utility. I am sure some will bemoan that any passing Russian warship is not met by a fully tooled up frigate with Harpoon at the ready, but why? It is only a case of marking them and showing a naval presence.