Was the impending Pearl Harbor attack known in advance?

[Lucky13]

What if they had sent up fighters when they first saw the Japanese coming? Did they spot them early enough to get them up to altitude?

[Njaco]

Radar was in its infancy and they had a few sets brought over from England but didn't rely on it much. They saw the blips and thought it was a fliight of B-17s due in from the mainland.

[syscom3]

Originally Posted by Lucky13

What if they had sent up fighters when they first saw the Japanese coming? Did they spot them early enough to get them up to altitude?

The Japanese were coming in at a middle altitude, so the time to climb wasnt excessive.

Unfortunatly, they were all pretty much destroyed on the ground quickly.

[Thorlifter]

Gotta side with the US knew something, but had no idea it was Pearl.

[Lucky13]

Isn't that the general belief that they knew that there were an attack going to happen but they didn't know where?

[syscom3]

The consensus was that a Japanese attack would start at the Philipines.

While some USN and US Army officers suspected that there could be an attack on pearl harbor, it was discounted.

In 1941, no one suspected that Japan could put together 6 carriers and execute a perfect strike on such a large and important military installation like Pearl Harbor.

[FLYBOYJ]

Originally Posted by syscom3

The consensus was that a Japanese attack would start at the Philipines.

While some USN and US Army officers suspected that there could be an attack on pearl harbor, it was discounted.

In 1941, no one suspected that Japan could put together 6 carriers and execute a perfect strike on such a large and important military installation like Pearl Harbor.

Agree 100%

[timshatz]

There was an interesting supposition about radar and what would've happened if the guy in the Operations Center (Kermit Tyler?) had hit the panic button instead of saying to the two privates "Don't worry about it".

The bottom line it came down to was....nothing much would've changed.

The US was not on a war footing. The guns for the planes weren't armed, the ships weren't ready, everybody was at peace. The first thing that would've happened (again, this was all supposition but it was fairly well thought out) would've been the contact report would've gone up the line, each guy passing the buck. That would've taken at least an hour if the chain of command (remember, it was Sunday morning) was efficient. It wasn't. That can be seen by the USS Ward sinking (not just depth charged but actually fired it's main armament at) a midget sub at 6:45Am and the commander of the US Pacific Fleet didn't find out about it until after 8am.

Even if the radar call had gotten down to the people in charge, they'd passed it along and everybody had done what they were supposed to do, the Pacific Fleet still would've gotten clobbered on Dec 7th.

In a way, they were lucky it happened in Pearl Harbor and not out in the open Pacific. As it was, the survivors from Battleship row and other sinkings only had to swim to shore (about 100yds away) instead of awaiting rescue in the middle of nowhere.

Not only did the machine shops, oil depot and submarines survive the attack, so did most of the personel in the Pacific Fleet. And those guys were the nucleas of the fleet that later destroyed Japan.

[renrich]

Nit picking but Salt Lake City was CA25 not CA24 which was Pensacola. Actually Halsey, in command of the task force in Enterprise, had them pretty much on a war footing because they felt that war was imminent. However, if the US had been aware of the IJN and the attack on PH and sent Enterprise and Lexington and the BBs to ambush them I think the US taskforce would have been lucky to survive. With only 2 carriers versus 6 Japanese our BBs would have been sitting ducks and the carriers may have both been sunk and the air groups decimated. Our carrier air groups were not nearly as efficent and experienced in December 1941 as they were in June 1942.

[Lucky13]

Which probably would have cost USN a lot more in sunken ships which they couldn't salvage.... Coral Sea and Midway might have happened a lot later instead, right?

[syscom3]

Originally Posted by Lucky13

Which probably would have cost USN a lot more in sunken ships which they couldn't salvage.... Coral Sea and Midway might have happened a lot later instead, right?

Coral Sea happened because of an impending invasion of Port Moresby. If the US took a couple of carrier casualties at Pearl, look for either the Coral Sea invasion to happen as planned, or no Doolittle raid on Japan.

If there was no Doolittle raid on japan, Midway might not have happened, and if it did, the US would only have a pair of carriers vs the Japanese 4 to 6.

[Lucky13]

If USN had taken carrier casualties at Pearl Harbor and be left with only two carriers and maybe less of other ships, could Japan have taken the chance and go for Port Moresby?

[syscom3]

Originally Posted by Lucky13

If USN had taken carrier casualties at Pearl Harbor and be left with only two carriers and maybe less of other ships, could Japan have taken the chance and go for Port Moresby?

They did in May 1942. The question is if the USN was going to gamble with its remaning carriers and stop them. If so, you could say the battle would end up as planned, but the upcoming Midway battle would be two carriers instead of 3. And thats if the IJN decided to go for Midway, as there were plans to thrust SE into the Pacific towards Fiji and Samoa.

[Wildcat]

Originally Posted by syscom3

They did in May 1942.

The Coral sea defeat ultimately forced the Japanese to attempt a land invasion of port Moresby by coming over the Owen Stanley mountain range. This campaign kicked off in July '42 and although the Japanese came close to reaching Port Moresby (IIRC 30miles?) they were eventually driven back and defeated by Australian Infantry. Do a search for kokoda track for more info.
Meanwhile in August '42 the Japanese launched a seaborne invasion on the Eastern tip of NG at Milne Bay. Again the Australian's defeated the japanese who were forced to withdraw making this I believe the last attempt by the Japanese to capture Port Moresby.
A question I have, The RAAF had two P40 squadrons at Milne Bay that was instrumental in the defeat of the Japanese. Not only did they provide excellent close air support (I've read the Japanese could hardly move during the day) but they effectively destroyed all the Japanese landing barges which left the Japanese unable to "leap frog" along the coast therefore unable to out flank the Australians. The P40's also destroyed a bunch of barges that had just dropped off about 350 Japanese soldiers on Goodenough Is therefore trapping them there and unable to take part in the action.
Back to my question, the Australian's enjoyed air superiority over Milne Bay because the Japanese were at the time concentration on the Solomons, in fact only a reletively few raids were carried out against the Milne Bay defenders, had the Japanese concentrated their air assest on Milne Bay instead, I believe it is highly likey they would have gained the upper hand, would this in turn lead to a Japanese victory? If so would Port Moresby fall next?

[HealzDevo]

I could remember hearing that radio messages were intercepted from the Japanese Carrier Group but it was thought to be a bluff the idea of a Pearl Harbour attack. There were coded references to it, by John Curtin's friend in the Documentary on John Curtin so I am unsure whether this is true fact. The true facts though will never probably be known of how much the US knew or suspected of Japanese Intentions before Pearl Harbour...