Remember the fact that over 70% of the world’s surface is covered by sea, 80% of countries have a coastline and most of the world’s population lives within 300 miles of the coast.
Great point. So how exactly is the Navy going to patrol all of that water with one carrier battle group when the other is in refit and hardly any spare Frigates/Destroyers?
The carrier group can't be in the Falklands, protecting the oil rigs in the North Sea, hunting pirates off Somalia, disrupting drug operations in the Caribbean, providing CAS in Afghanistan (or whatever conflict we get drawn in to next) and flying the flag elsewhere all at the same time. Yet if the carriers are built then with such a limited number of FF/DD the surface "fleet" will be limited to being in one place at one time protecting the carrier. So we get to pick one battle and hope nothing else is going on at the same time.
If we had the money then great, but we don't and putting all of our eggs in one carrier shaped basket is short sighted.
A logical assumption is that the Navy is playing the long game here and reason that in a few years time they'll be in a better position to argue for an increased fleet. But when this is likely be at the cost of capabilities in the other services and also reduces our total defence capability across the next decade - and this includes the Navy since it could do a lot more with a large fleet of FF/DD rather than the carriers - then it is about single-service empire building rather than defence of the realm.