I don't see any argument with the replies.
Politicians are a strange breed, with a very limited life span. They react in a self serving manner, which can be channeled by money and the media.
As regards mission, consider the name "Nimrod" should have been reserved for a Maritime aircraft, and never given to the "R" variants. Call them "Big Ears" or "Hertz Vacuums". Consequently the politicians can't distinguish between MR's or R's, and the UK politicians, eager to please Washington promise them "Unrealistic Expectations" to continue the myth of a Great Warrior Nation, with a seat at the Superpower table. In the meantime the world's oceans are becoming the playground for pirates, terrorists and Russian submarines, en route to China.
I would even say scrap the MR4 and buy the P8A, everyone else will. Use the money saved to develop a couple of squadrons of smaller, faster surveillance aircraft, based on existing civilian airframes that can patrol the waters around the UK, Med and Middle East. Stop looking for Soviet "Boomers" or planning to support Hong Kong and Singapore.
Yes, I believe it's time to say RIP to this thread, and open another to look ahead to future threats, future cost-effective platforms, and allow the able serving people to quietly correct the problems that caused this thread to be created. Give the politicos ideas for their speeches, not criticism of things they don't understand anyway!