The simple fact is that a) fisheries have been a Navy task since 1481 and b) there have been attempts in the past to create a "proper" Coastguard, but they all foundered on the issue of who would get the money in their budget. As the roles are currently spread across a number of different departments, it would involve taking both responsibilities and budget away from some departments and giving it all to a single department - and as we all know size IS important (just to be clear, I'm talking about departments here
).
The thought occurs to me though - maybe with "he who shall not be named" weilding his departmental chopper, now would be a good time to rationalise. With the example of DfID fresh in minister's memories, they will be happy just to lose little bits, rather than their whole department.
Who would you want to run it, though - the existing Coastguard Agency and SAR is run by the DoT - once you include the Border Force (Home Office), offshore Customs and Excise (HMRC, technically a Department in it's own right, but without a minister), Fishery Inspection (MAFF, partially subcontracted to the RN), Marine Policing (Home Office), offshore Pollution monitoring and control (DoE) etc. etc, there's a lot of losers and only one big winner.
The pessimist sees difficulty in every opportunity. The optimist sees the opportunity in every difficulty.
Winston Churchill