Having large, heavily armored warships was a tactical advantage in the 20th Century.
But as military technology and weaponry advanced, battleships became obsolete. Battleships were the apex of power in the era when gun battles dominated naval fights, and they still proved useful for decades in firing retrofitted missiles and hammering enemy coasts with guns. Each 16-inch gun could fire a round that weighed around 2,000 pounds.
Less than a dozen battleships are still afloat in the world — eight of which once belonged to the US Navy — now serving as museum ships honoring the historic battles they served in.