Why is there so few aircraft carriers?

Answer 1

The cost of upgrading older ships to bring them up to modern standard is estimated at about $200 million and one year in the shipyard. The cost and return was deemed inefficent in view of the current poitical climate.

Answer 2

In World War 2 there were few aircraft carriers because the US had not built up their aircraft carrier fleet because the Americans were not willing to fight in the war. Now we have thousands of aircraft carriers around the world. Oh, in the Forties the use of aircraft carriers was still relatively new. They still thought destroyers won the wars when in reality it is the aircraft carriers that do the bulk of the work.