Utah, even after being disarmed, looked like enough of a BB for her to get two torpedoes.
Anything afloat would get hit by
IJA (err IJN) pilots with 'Buck Fever'
Didn't the Japanese pilots confuse the Utah with the Saratoga due to a cover over the ship that made it look like it had a flight deck? Or is this another PH myth?
Hypothetically, the USS Saratoga could not have been damaged by I-6, on January 11th, 1942, but sunk, so lost forever. USS Wasp, ferrying spitfires to Malta could have been lost similarly as HMS Eagle on august 11th 1942 in the same region to a submarine attack as well, so not available. USS Hornet, was still on a shakedown in the Caribbean Sea, possibly being hit on the East Coast as well by marauding U-Boats.
That would leave only the USS Yorktown available, as she had already departed quickly to the Pacific, prior to the U-Boats starting their assault on the US East Coast.
HMS Warspite, there is no one on AH.com who knows more about the technical aspects of warships than you. However, US fleet CVs did have considerable escort. And as you know better than I, one reason that the Sara was such a torpedo magnet was her turn radius being poorer than the Yorktown-class and Essex-class. The Wasp was slightly slower than the Yorktowns, but not by much. Her loss OTL was much due to her being put in the position of constantly patrolling on the same course pattern day after day, allowing intrepid Japanese sub commanders to take advantage. IDK however how her turn radius compared to the Saratoga-class. The Ranger was probably the worst. But again, you would know better.
I don't see all these carriers being torpedoed AND sunk one after the other short of Skippy issuing the the Kriegsmarine AND the IJN Mark 48s (or even Spearfish

) AND the USN getting a case of the criminal stupids by not changing their OTL operations. Your ATL doesn't give a time for the sinking of the USS Hornet, but it would HAVE to be prior to the USS Wasp's mission to Malta, as OTL the Hornet was already long in the Pacific by the time of the delivery of the Wasp-borne fighters to Malta.
IF the Sara is lost AND the Hornet is lost quickly afterwards (lets say so quickly that the USN doesn't have time to react regarding the Hornet's deployment), then by any reasonable standard the Malta mission is a wash. The only way that that could be avoided is if the RN reverses its decision to NOT send any of its three carriers operating off the African coastline to the Coral Sea. (1)
1) The Admiralty's refusal of Admiral King's request to redeploy any of those carriers to Australia making a lifetime enemy of the already anglophobic King was a mistake Churchill only realized later.
So either its Royal Navy carriers in Australia (with a subsequent delayed occupation of Madagascar) or Malta is further starved while the Wasp rushes to the Pacific.
I do agree with those who say that the USS Ranger stays in the Atlantic. Not for air support for Torch so much, or its value as a training ship for USN aviators, or even to calm panicky Americans on the East Coast

. Rather, because Ernest King was pathological about keeping Ranger out of harm's way. (2) Since she was the first US carrier designed from the ground up, she was built for aircraft capacity above all, allowing for 72 aircraft on a vessel that on any other carrier design for a ship that size would have had perhaps half that complement. The cost being virtually no protection from torpedoes, and a metal flight deck only one inch thick! A one hit wonder, more in common with a light carrier than a true CV.
2) So pathological that he was forced to swallow his enormous pride and accept the deployment of the HMS Victorius/USS Robin to the Pacific to fill in the gap when at a time the only operational US carrier left was the Enterprise. Better King be humiliated than risk the Ranger against the Japanese. IIRC, the Ranger was never brought within enemy air range in WWII (though I have a faint memory that she might have seen action in Norway).
As to the Japanese? ITTL the USN simply doesn't have the wherewithal to do very much. I just don't see the Wasp being deployed to the Med in a world where Enterprise, Lexington, Saratoga, AND Hornet have been lost. Oh yeah, and the Langley too.

Just a seaplane carrier by then, but the political perception is there of "there goes another one". OTL much of the aggressiveness of the USN in the first year of the Pacific War can be based on the following:
a) Starting the war with an intact force of seven Fleet CVs (with one permanently spotted in the Atlantic).
b) The need to send the carriers into combat to actively give the aircrews the baptism of fire they so desperately needed
c) The need to bolster the morale of the military and the Home Front.
d) 1942 was an election year.
e) See "d"
I believe that at the very least some of the pinprick raids will have to be done. They're not really dangerous, and Hawaii defense can be handled by the garrison and shipping or flying in every last combat aircraft to the Hawaiian Islands as the facilities there can handle. Even Lend Lease will take a back seat to protecting Hawaii ITTL. At least in terms of fighters. As to the Doolittle Raid, I believe FDR will force that on the navy anyway ITTL. It would just be a matter of co-ordinating the pinprick raids and preparation for Doolittle. FDR's thinking would be that if he doesn't give the Americans SOMETHING before Election Day the US House is going to go Republican (he only kept the House by 42 seats).
OTOH, it means Port Moresby falls to a virtually unimpeded Japanese assault.

OTOH again, Yamamoto did not consider that the two fleet carriers employed in the Coral Sea were needed at Midway, so maybe the operation doesn't happen as some kind of ATL overwhelming force. I don't know. I'd appreciate your opinion on that, and what would be the results.
The only things I am certain of are these: Midway and New Caledonia are both too distant and too heavily defended for the Japanese to take. Fiji and Samoa are too small and too difficult to properly supply for the US to hold. But Midway, considering the force Japan was bringing to bear on the island, could take whatever the Japanese threw at it. New Caledonia would represent an exercise on how to slaughter troops on the beaches. Japan's intelligence on that island was criminally inept.
If Ranger and Wasp are pulled out of the Atlantic earlier to replace Lexington and Enterprise that means that fewer Spitfires are flown off to Malta in the case of Wasp and less air cover available for Operation Torch in the case of Ranger.
Its not like air power was all that critical at Torch, considering how fast the Vichy switched sides.
Is it feasible to have Saratoga at Pearl Harbor when the Japanese attack too?
AIUI, the Saratoga had a number of obsolete aircraft it was having transferred off (F3F's? Vindicators?) and therefore really couldn't get to Hawaii that quickly. Like at Midway, she was just too late for the action.
OK, so let's say Lexington and Enterprise are at Pearl Harbor. Does that mean that KB delayed their attack by 24 hours?
No. Too short of fuel. Using the North Pacific route gave the KB strategic surprise, but it also did a number on the fleet's fuel reserves.
Nevertheless, if everybody is home. Lexington is moored on the NW side of Ford Island, behind Utah and Enterprise is moored where Neosho was OTL (between California and Oklahoma), sitting at an angle to the battleships. This was their usual mooring spot when in port.
Lt. Nagai's force of 16 torpedo planes were designated for the carrier attack and he is approaching from the WNW (directly into the sun). 2 of 6 torpedoes launched at Utah hit the target (1 of the misses hit Raleigh), which shows the problems caused by attacking into the rising sun. So, let's say Fuchida recognizes the carriers early and notifies Nagai to attack carriers. I assume he would attack Lexington with 8 aircraft and loop the other 8 around to the south to attack Enterprise.<snip>
IIRC, the timing was such that the torpedo planes came in so quickly that such surgical maneuvering over a battle site in 1941 would have been impossible. Fuchida couldn't assume that there weren't American fighters deployed on airfields on other nearby islands winging their way to Battleship Row at that very moment. The idea was to go in and hit hard before the US warships could react.
As it was, the Kaga's torpedo air wing suffered the severest losses in the attack because they approached in line with another strike force, causing any American AA fire missing the aircraft in front of them to hit the torpedo planes behind them. I remember watching one very old IJN Kaga torpedo plane aircrew veteran saying: "Everyone talked after the attack how light our losses were. You didn't say that if you were in the Kaga's torpedo plane squadron."
Does Fuchida change the attack plan due to the presence of the carriers? I doubt it, because the attack plan already had that contingency and allocated 16 torpedo planes to the carriers. He does have 36 dive bombers with 250 kg general purpose bombs in the second wave allocated to shipping targets. He would probably allocate some number of those to the carriers for sure. How destructive would they be and what would their hit rate be? Enterprise is certainly going to be shrouded in smoke.
A sitting duck is a sitting duck.
Does this necessitate the 3rd strike? It is my understanding that Fuchida and Genda wanted it in the first place, but do they get it? If Nagumo now knew where the carriers were at Pearl Harbor does he relent? And, if so, how much of the smaller 3rd wave is allocated to shipping versus infrastructure? Even if, I do not buy the premise that the Fuel farm is lost for a year. The article referenced talks about replenishment oilers, not the tankers used to supply PH (reasonable mistake for a USAF officer). Operational reach is a different issue than the ability to rebuild and resupply a fuel depot at PH.
Fuel logistics more than anything bar a third strike. If a third strike HAD been launched, then some of Nagumo's ships aren't getting home. He was under strictest orders (from the Navy Ministry IIRC) to get his fleet home completely intact, despite the expected losses of at least one or two of his carriers. As it was, OTL, three of his destroyers had only three hours worth of fuel left in their bunkers by the time they reached port (the weather going home was even more stormy than getting to Hawaii in the first place). Losing your ships in combat is one thing. Losing some of your ships because they ran out of fuel and foundered at sea in a North Pacific storm (to be lost with all hands, that water will kill you in minutes) is the supreme dishonor,

even with all the "glory" Nagumo had gained. If nothing else, it will mean much less respect for Nagumo, and more for his aviators.
Something similar happened to a force of German destroyers in Norway, where 10 DDs were lost when they ran out of fuel, just as a British battleship showed up loaded for bear. Similarly, a British Royal Navy officer was disgraced when he decided to launch a force of Spitfires by air to Malta when the fighters were outside of their effective air range. Every plane was lost.
Even if Moresby falls, does that prevent US troops and supplies from reaching Australia? No!
But it does mean that NE Australia gets the same 200 days of bombing that NW Australia's Darwin did. And there are more people living there if I'm not mistaken.
Does that prevent the US from attacking westward in 1942? First, they didn't have much reach to begin with so the major offensive crossed off the list is Guadalcanal, and should make the Doolittle raid too risky.
I agree with you about Guadalcanal, but we'll agree to disagree about Doolittle.
What about Kwajalein? That actually fits better with Navy plans anyway and scratches the "do something" itch; and it is within range of the West Coast.
I disagree. With such a pummeling of the USN, IMO Dougout Dougie wins the argument years earlier and gets the men, aircraft, and ships he needs to start his own island-hopping campaign. Having Halsey as his naval commander would be a huge plus, as against all expectations OTL the two men became fast friends.
The advantage being the use of Australia as an unsinkable aircraft carrier and allowing the USAAC to be brought to bear against Japan's critical oil sources in the DEI. Though the price may be that the 5th Air Force (and accelerated Lend-Leased aircraft to the RAAF & RNZAF) will dampen the US's efforts at daylight strategic bombing for quite some months.
IIRC, the Japanese carrier Ryuho had neither when she was attacked in port in March 1945, and yet the damage was so severe that the IJN declared her a total loss. Not that it mattered much, seeing as how at that point the IJN had been totally stripped of planes, pilots, and fuel.
Wasn't she damaged during the Doolittle Raid but was able to be repaired and eventually returned to action? IIRC she was just about the only flight deck the IJN had that wasn't available for Midway because of this reason.
No one has mentioned the escort carriers. If two fleet carriers are lost on the first day of the war could there be a push to get the CVEs in action earlier? Perhaps they could patrol around Hawaii? If there is still a Guadalcanal landing the CVEs could help cover the beachhead. The bad thing is you get an earlier version of Taffy 3's fight at Samar.
Combustible. Vulnerable. Expendable. Oh yeah, and Slow. They run into fleet ships, whether surface or carriers, and there's nothing to do but pray. They simply lack the speed to escape. Short of having overwhelming numbers. CVE's are for ASW, tactical air support, CAP, pilot training, and best of all early in the war, aircraft ferrying. The USS Long Island, the USN's first escort carrier (and around long before her sisters started to arrive) did yeoman service in the Guadalcanal Campaign through her keeping up a constant flow of planes to the "Cactus Air Force".
Something else to remember is this: By the end of 1942 the US Navy only had Enterprise left in the Pacific OTL. The US still hung on.
ITTL maybe the British do more to right their Madagascar error by sending more CVs than HMS Victorius/USS Robin, and for a longer time?