Random thoughts..
Neither of these were states in 33.
Not sure why they would NEED more preparation. Nothing big happened that preparations would have stopped.
Peril Harbor was not a result of not having defenses in place it was a result of a sneak attack during peace time and on a Sunday (a day that was much more significant back then as pretty much no one worked Sunday that wasn’t a 24/7 type of job and even 24/7 jobs used skeleto crews on Sunday.
And the “invasion” of Alaska was Japan find a pretty useless location if no significance and landing on it. As big as Alask is and as many islands as it has no reasonable preparations will stop that either,
So what is it we want to accomplish ?
Given unending money and cooperation with/by Canada it would have been Nice to build a joint Railroad/road instead of the Alaskan Highway. That would have helped Alaska in the war and after. But as I said it was not like Alaska was in danger. Nor was it all that much use in 1941-46.
As for Hawaii…. About all I can think of is building more storage facilities for weapons and soars and oil and such. They would need to be hardened. But you are not preventing Dec 7 by building anything. And radar was not really an option nor was it important in 33. By important I mean no one in 33 was launching an Air raid of significance on Hawaii so even if we could have built a radar system like chain home in 33 there was no threat to detect. Now in 38 it was theoretically possible to build (as Chsin Home was under construction) but it was not a US thing. And the threat was not at that level. Even in 41, the gamble that Japan took risking its fleet to hit Peril was huge. We sometimes miss that it was a huge risk because we A) know it worked and B) we know how dominate Aircraft we’re in the Pacific. But in 41 that was not known.
But I suppose with unlimited funds and man power..
I would start in the 33 expanding the dock and supply bunkers and such. Expecting that when the war starts I will need to increase the personal and such in Hawaii 10x. So prep for it. Newer bigger barracks. Enlarged Hospitals. Big repair fasilities huge reinforced warehouses etc.
As the war gets closer add as many Anti Aircraft guns as I can get all over the place. Once WW2 starts in Europe take the lessons from the blitz and try to make Hawaii resistant to Air Raids.
And as soon as the tech allows for it start building Radar to give 360 coverage and reduntent coverage and keep them mailed 100% of the time.
And still…. You won’t save the fleet, you may knock a few more aircraft out of the sky but you won’t save the fleet. Still as it turns out the weak point of Japan was trained pilots so anything you can do that costs then this rarest resource is a good thing.
But in truth Spending money on Hawaii is not a great plan unless you know to enlarge the capacity of the bases. More dry docks would be great..
And any money you spend in Alaska is frankly a waste. I would only spend it there if it was spend it in Alaska or you don’t get it. I would much rather spend the money push other projects. More destroyers would be a good use. Or. Here is a strange idea.. increase torpedo production and i know this is going yo sound crazy… test the damn things.