I was recently reading about the 1937 Battle of Shanghai, and the frequent Japanese use of Naval artillery to offset the lack of land based artillery available to army forces on the ground.
This made me wonder, how effective were WW2 naval vessels at providing artillery support to ground forces? Obviously if, for example, HMS Warspite were to land a hit on an infantry position with a 15 inch naval gun, the result would be devestating, but would she feasibly be landing enough hits to actually make her presence worthwhile?
I'd imagine artillery fired from an unstable platform, pitching in the ocean, shooting inland at a target it could not see, most likely co-ordinating with a forward observer from a different element, would have incredibly low accuracy.
So, how effective was Naval offshore bombardment during the Second World War? Did certain belligerents employ specific tactics to make it more effective then others? Or was the psychological impact of the existence of this large caliber support more important then actual results on the ground?
Thanks!
One factor that was only touched on by the linked answers provided by thefourthmaninaboat is that shore bombardment was an art that, much to various navies' surprise, required specific experience and training. In the Pacific Theatre, which saw a much higher number of bombardments and landings, USN slow battleships (i.e., World War I veterans, modernized to varying degrees) often inflicted more damage than more modern fast battleships, because the former were more often used for shore bombardment while the latter spent their time as carrier escorts.
A quote from Samuel E. Morison is pretty instructive:
Sad to relate, the bombardment of 13 June [1944, against Saipan] was a failure. These fast battleships simply did not know the technique. They had been too busy steaming around with carriers to practice bombardment, a type of firing that requires slow and patient adjustment on specific targets, differing widely from main battery fire in a naval engagement. Pilots of the battleships' spotter planes had not learned to distinguish targets. And the battlewagons were required to shoot from ranges between 10,000 and 16,000 yards because they were considered too valuable to risk in the unswept shoal area which extends about six miles to leeward of Saipan. The result was that most of the 16-inch and 5-inch shells went completely wild, and the only targets destroyed were large, conspicuous, and of no military value, such as farmhouses and the Charan Kanoa sugar mill. Actually 2432 high-capacity 16-inch and 12,544 five-inch shells were expended in all this sound and fury. There was much truth in a humorous bluejacket's description of this bombardment as "a Navy-sponsored farm project that simultaneously plows the fields, prunes the trees, harvests the crops, and adds iron to the soil."
The limitations of naval gunfire developed from battleships was one reason for the development of specialized bombardment craft, like the US 4.2-inch mortar gunboats. These were, quite literally, a handful of heavy rifled mortars attached to a landing craft, and they were capable of bombarding just a few hundred yards ahead of advancing infantry--something heavier ships could not do safely.
I've previously answered this question here and here, though more can always be said. This answer on how naval bombardments were carried out might also be of interest.