2. A carrier group can take weeks to deploy to the scene. A bomber can be there within 24 hours - worldwide.
A carrier can reach speeds of over thirty knots = which means it can sail well over 700 miles per day - in the USN's case they don't need to stop and refuel as they are nuclear powered. It won't take "weeks" to deploy - a week maximum. By contrast how long does it take a single squadron of fighters to deploy, work up, get spares / munitions in and be ready to fight? At least one week - multiply that by 4 and you have 50 odd aircraft all needing basing rights, fuel supplies and personnel. Thats the same as one carrier.
Yes the bomber can be there in 24 hours - but given that a SINGLE B2 costs well over $2 billion don't you think there are more efficient ways to spend $40 billion than on twenty bombers?
As for Diego Garcia - this time we were lucky and had a handy base in the locality - next time we might not be so lucky - we take our land bases for granted at our peril.