In a Strategic Review presumably they have to think of likely threats
we currently have obvious ones - terrorism, piracy (Afghanistan is reaching the departure lounge)
we have potential threats such as Iran & the Gulf , Falklands maybe
we have the potentially really scarey stuff - Korea, Taiwan or Georgia for example
then we have the stuff that just pops up- hijackings, earthquakes, famine
are we going to have an all round , world-wide reach capability or not???
Lets face it any ship (e.g Type 45) built today will probably still be in service in 40-50 years and I'll bet the C-17s are still around in 20-25 years so you have to take the long term view - which politicians are famous for doing.....