keesje,
I'm not sure what you mean with your last post regarding A330, A400M, F22 and F16.
Duncan those are dominant "jack of all trades". The MRTT is a tanker transport, the A400M a tactical-strategic transport-tanker, the F22 a stealthy strike-air superiority platform and the F16 the classic fighter-bomber.
Contrary to the Typhoon fighter (that has yet to become a good attack aircraft, if ever), the Nimrod ~dedicated ASW, VC10 ~ a dedicated tanker and Tornado IDS a strike, ADV a ADV aircraft.
The USAF made the switch to with the KC-X. The previous 700 KC135s primairy task was waiting for a large scale tanker supported operation. The KC46's will make many more hours doing people, pallets and containers, at less then half the cost a C-17 can.
IMO the best way to prevent a new MPA for the UK happening is to basicly copy 1983 requirements and say a domestic product must be developed to fulfill the UK's unique requirements and its historic role on the Ocean.. Killing.