Battleships were at the core of the first modern arms race in the early 20th century. This battleship arms race began shortly before the outbreak of the first World War (and many historians believe helped to cause it). But the reign of the battleship ended decisively with the attack on Pearl Harbor.
The idea of a large ship, carrying primarily big guns, goes back to the days of sail. These were called "ships of the line", because the tactics of the day required bringing a line of several ships broadside to the enemy, and blasting them with the cannons mounted on the sides (a "broadside").
The tactical goal in those days was to "cross the enemy's T", to maneuver so as to have the enemy sailing straight toward the side of your ship. The front of these vessels were poorly armed, having at most only deck-mounted hand cannons. Therefore the firepower of a broadside would likely destroy the oncoming enemy ship, with little harm coming to the ship crossing in front of the other ships.
Below, two lines of warships ("Battle ships of the line") firing broadside volleys at one another.
In theory (and in practice), the larger ships with bigger and more cannons would typically sink smaller and less well-armed vessels. The best defense for a smaller vessel was to rely on speed to escape, or maneuverability to avoid a broadside, if possible.
Below, a sail ship with three rows of cannons
The term "Battleship", while coined during the age of sail, became more common when steam-powered ironclads came onto the scene. Ironclads were the ship-builder's response to the introduction of incendiary and explosive shells, which of course were highly destructive to wooden vessels. Additionally, naval cannons were becoming more and more powerful, and later models could blast through several inches of oak, sending wooden shrapnel flying inboard to kill the crew.
This Union ironclad (USS Cairo) appears to have an armored stern wheel for propulsion. This was a ship used on the Mississippi River during the US Civil War. Most deep-water ironclads used the newly invented (and less vulnerable) underwater screw. Note the angled sides, intended to cause incoming shells to deflect rather than penetrate.
Ironclads, and all battleships made up until the introduction of the HMS Dreadnought are considered "Pre-Dreadnought" designs. The difference between an ironclad and a dreadnought-era battleship is the use of wood underneath the outer iron skin. Typically 8-12 inches of wood would underlie 4-5 inches of iron or low-quality steel cladding on an ironclad warship. Ironclads were not particularly fast, nor were they maneuverable. They used piston steam engines rather than turbines for propulsion.
HMS Dreadnought was such a technological marvel that even decades after she had been scrapped, battleships were called "dreadnoughts". Pretty impressive!
Below, the ship that started an arms race.
HMS Dreadnought made all warships that had come before obsolete. She was very fast, because she was the first warship to use steam turbines for propulsion, and thus she could run or fight on her own terms. Secondly, she was the first battleship to use only large (12 inch diameter) guns.
In the era of HMS Dreadnought, fire control consisted of spotters checking for splashes in the water where shells landed, and then advising the gun crews how to adjust their fire to get closer to the target - and maybe even hit it! Ships that had a variety of gun sizes would often confuse the spotters, who might see a splash and not know which size of gun battery had fired it, making targeting confusing. On a ship with all large guns, this issue of confusing splashes from large and small guns out on the horizon did not arise.
However even during the heyday of this arms race, a fearful enemy hid just under the surface, and that was the submarine. Every battleship captain's nightmare was that his gleaming, magnificent, treasury-busting ship-of-the-line would be sunk by a lowly torpedo. If you look at the photo above, there are a series of poles running alongside the ship. These would be extended when the ship was not in motion, and torpedo nets would be hung from them. Not as invulnerable as they seemed, then.
Deploying torpedo nets.
The United States (finally moving to steam turbine propulsion in 1922):
So the naval powers of the world, just before the Great War, embarked on the business of bankrupting their treasuries to build fleets of mighty battleships, just as the emerging technologies of air power and submarines were about to render them nearly useless. And while naval strategists envisioned battles of all big-gun ships, during actual (as opposed to theoretical) wars, most of these ships succumbed to mines, torpedoes, or air attacks.
One of the few battles fought with large-gun capital ships was the Battle of Jutland, in 1916, off the coast of Denmark. The larger British battle fleet engaged the German battle fleet over the course of two days, with the intent of sinking them or keeping them contained in their home ports. The British lost twice as many men and tonnage than the Germans did, while causing the Germans to retreat home. Both sides claimed victory, although one could also say that both sides lost.
After the German fleet exploded three of the British Dreadnoughts, David Beatty (commander of the British Battlecruiser fleet) turned to his flag captain, saying "Chatfield, there seems to be something wrong with our bloody ships today." He was correct. British designers and the Navy had traded the weight penalty of thick armor for greater speed and more guns; the British battleships were little more than very expensive floating bombs.
Even though the battleship had proven itself not terribly useful during the Great War, maritime nations continued to build them. There was even a sort of battleship arms control, with each nation allowed to build a certain tonnage of battleships and aircraft carriers.
Below, the German Battleship Bismarck during WW II. After her rudder was damaged by torpedo bombers, the British battle fleet caught up to her. She was then sunk by both enemy gunfire and intentional scuttling.
What finally did the battleship in though, was the eye-opening events of December 7,1941. On that day six aircraft carriers sunk four battleships, damaged four more, and sunk or damaged several cruisers and destroyers, in addition to wreaking havoc on the airfield at Ford Island.
Below, Pearl Harbor at the beginning of the attack. Ford Island (center) sits at the center of Pearl Harbor. In this photo, the battleship West Virginia has just been hit by a torpedo.
USS West Virginia
USS California (Neosho behind)
...you get the idea...
No number of battleships could have accomplished the destruction that these six aircraft carriers did. Even if the Pearl Harbor battleships had been at sea, they could not even have gotten near enough to the aircraft carriers to harm them without being sunk by torpedo bombers first. Battleships were quickly cast aside, in favor of aircraft carriers and submarines.
In between wars, battleships were gaudy, impressive, and threatening. During an actual shooting war, they were quite a bit less fearsome, spending their time bombarding tropical islands and escorting the more strategically valuable aircraft carriers.
Meanwhile during World War II, just 314 US submarines sank 1560 enemy ships, an impressive 55% of the total tonnage sunk during the war.
And so, suddenly after one Sunday in Hawaii, the future of naval warfare turned to submarines and aircraft carriers (and the many, many ships required to protect aircraft carriers).
Oddly enough, in spite of these lessons of history, US battleships gained a third lease on life toward the end of the cold war. Four decommissioned battleships that had been built during WWII were recommissioned, and refitted with guided missiles and also with close-in weapon systems for missile defense. These ships were decomissioned the second time in the mid 1990s.
Iowa fires a broadside in 1982 for a firepower exhibition. Exhibition... that kinda says it all.
Now as unimpressed as I am by the usefulness of battleships in actual battles. I still think they are cool. Extremely cool. Just sayin... Check out that armor. 17 inches of steel!
USS Missouri ("Mighty Mo") after her 1980s refit with missiles and modern electronics. Also, 33-35 knots is pretty darn fast!
In closing, I honestly believe that if the navies of the world were to engage in unrestricted warfare, *nothing* would be afloat on the surface within a week. Only land-based aircraft and a handful of very advanced submarines would remain.