From: Arnhem (holland) yes a bridge to far...
In 1939 there was no NEED for those BIG coastal bombardment ships which you discribe. This role was already fullfilled by simple and cheap GUNBOATS that could simple steam up a river to bombard some backward inner country city.
The British had their pre war Erubis and Terror monitors which could crawl to places to bombard (these ships where SLOW and highly vurnerable with their box shaped hulls). In the pacific these ships where totally inpractible as the distances there where so big. If you really wanted to have bombardment ships, it would have been cheaper and more practicle to keep those old BB's in commision as bombardment ships....
Creating permanent gun emplacements, is COSTLY. It does not mean "just" putting a turret somewhere, but you will also have to build armored power plants and ammo storage for those turrets. These fortifications will also have to be staffed and maintained, costing even MORE.
Permant coastal defense fortifications where only feasible in high risk and high value places like Manilla, Pearl, Singapore etz. Wake (like Guadacanall) was certainly NOT high value in 1939.
In vinum illic est sapientia , in matera illic est vires , in aqua illic es bacteria.
In wine there is wisdom, in beer there is strength, in water there are bacteria.