Aircraft Carriers Aren't Cheap.

A detailed explanation of the costs of old and new aircraft carriers is set forth here.

Bottom line: An next generation aircraft carrier design is expected to cost $8.1 billion each (a highly optimistic estimate), plus a one time R&D cost of $5.6 billion (again, probably an understatement of what will really happen if one is built). A new aircraft carrier built to current designs would cost $8.5 billion to build. New aircraft carriers are expected to save about $5 billion over 50 years in operating costs, mostly due to smaller crews (about 500 fewer sailors per ship) and lower maintenance costs (mostly due to changes in the catapults for aircraft launches, the bilge system and the ease with which electrical systems can be upgraded).

Of course, even this multi-billion price tag is deceptive. Buying an aircraft carrier is like buying a computer. When you buy a computer, you also need a monitor, speakers, a printer, back up power supplies, software and more. When you buy an aircraft carrier, this isn't a stand alone purchase either. As I noted at dkospedia:

The Navy's notional carrier battle group has six surface combatants, an aircraft carrier and its air wing, two nuclear attack submarines, and a fast combat support (logistics) ship. In practice, aircraft carriers (and their air wings) are typically deployed with two cruisers and two destroyers, plus a frigate or two, a logistics ship and a nuclear attack submarine, or with one cruiser and four destroyers, plus a frigate or two, a logistics ship and a nuclear attack submarine.

An American full sized aircraft carrier typically has about 8 helicopters (perhaps double that in some case as fixed wing anti-submarine warfare planes are phased out), about 8 electronic warfare airplane (half for jamming and half providing sensors), and about four dozen fighter aircraft (either F-18s or F-35Cs), as well as a small cargo plane designed for use on carriers. As many as about 85 aircraft could be carried. An F-35C will cost about $40 million each, and the other planes run from the high single digits to low double digits of millions of dollars each.

Nuclear attack submarines run about $2-$2.5 billion each. Cruisers and destroyers were running about $1 billion each, but the DD(X) is scheduled to cost far more than thatamountt, and the littoral combat ship which will replace the frigates in manyroless will cost $200-$250 million each. Advanced logistics ships probably cost at least $100 million themselves.

All told, outfitting an aircraft carrier group costs in the vicinity of $17-$18 billion, plus R&D costs and operating costs, and could cost far more if we insist (contrary to current plans) on replacing the existing destroyer fleet with far more costly new versions. To buy a dozen of these, as most hawks would like to maintain the, until recently status quo force, is a $210 billion capital expenditure (including R&D) plus massive operating costs (although reduced crew requirements mean that operating costs for newer ships will be considerably smaller than for our current aircraft carrier fleet).