Despite aircraft carriers immense cost, the Navy believes there is no replacing a well-armed, aircraft equipped, sovereign piece of U.S. territory, powered by dual nuclear reactors.

Former Defense Secretary William Cohen was fond of saying that without "flattops" the U.S. has "less of a voice, less of an influence."

Perhaps, but there is another school of thought that questions the wisdom of floating something that expensive within range of an attack that may send it to the bottom of the sea.

Despite which group you fall into, carriers are likely here to stay as the U.S. works to replace its aging fleet with the new Ford class carriers and China builds up a fleet of its own. We thought we'd take a look at the carriers each country has in service today.