Sure, they could do this and indeed, I even expect them to; such, however, makes Operation TORCH impossible as I said previously by stripping it off air cover. It would be under the aegis of a Pacific-First Strategy, necessarily.
I have a lengthier reply to the rest of your two posts, but for the moment I have the time to address this point, since it's a straightforward factual clarification which can prescind from larger strategic considerations. I can't help the impression that you have a truncated view of Allied air assets employed in TORCH, and this has created some strategic confusion.
1) Naval assets. A total of 12 aircraft carriers were employed in TORCH: 5 American, and 7 British.
Western Task Force: 1 Fleet Carrier (USS Ranger) + 4 escort carriers (USS Suwanee, USS Sangamon, USS Chenango, USS Santee)
Eastern and Central Task Forces: 4 Fleet Carriers (HMS Formidable, HMS Furious, HMS Victorious, HMS Argus) + 3 escort carriers (HMS Avenger, HMS Biter, HMS Dasher)
2) Ground Based RAF and USAAF assets. In fact, most of the air cover for TORCH was not naval. 466 RAF and USAAF aircraft had been assembled at Gibraltar, and these provided additional air cover and then began landing on Day One at captured airfields in Morocco and Algeria. After the initial landings, these came to provide almost all of the air support for TORCH ground operations.
As we can see in turn, only one of Somerville's three fleet carriers ended up being used in TORCH - HMS
Formidable. HMS
Indomitable was sent off to take part in PEDESTAL, where she received two 500lb bomb hits courtesy of the Luftwaffe, and HMS
Illustrious remained to undertake a decoy operation against the Andaman Islands while WATCHTOWER was underway. Thus, transfer of
Illustrious to the South Pacific remains the really obvious initial redeployment. Honestly, it's a no-brainer.
Let's turn to TORCH. Given the forces that Cunningham had to cover the landings at Algiers and Oran, we can see in turn that the loss of one British fleet carrier - if that is indeed in contemplation - is hardly fatal to TORCH. If that's
Ranger, that's 72 aircraft (1 CRAG, 17 VS-41, 26 VF-9, and 28 FV-41). If it's an
Illustrious-class deck, that's a mix of 36 Fulmars and Albacores. Obviously, the British deck is a more bearable absence.
We do not have any agreed list of combat losses in this Alt-Midway - though presumably Nimitz has lost at least two of his carriers. The scale of the losses could affect just how the US responds in terms of redeployments, but the most likely outcome, I think, is that USS
Wasp is sent to the Pacific immediately, thus giving Nimitz at least two fleet carriers (
Saratoga, Wasp), and three if there's a survivor from Midway, while
Ranger is kept for the Western Task Force of TORCH, where she accounts for too big a slice of US air power for the initial landings to easily dispense with, and makes the most sense for integration into an otherwise wholly US naval task force. After the TORCH landings are concluded - which in this timeline is now more like mid-October - it's near certain that
Ranger and the CVE's get sent to the Pacific immediately.
The question then is whether Churchill would order Somerville to immediately send
another one of his
Illustrious-class decks to Nimitz in June, or more to the point, what the consequences would be if he did. At least one has to get sent to the Med for PEDESTAL. It can be a reasonable working assumption that this carrier suffers what
Indomitable does in our timeline, which means a risk of effectively losing an
Illustrious for TORCH, which would remove about, roughly, one sixth of Cunningham's naval air cover for the Central and Eastern TF's. It is possible, though, that
the damage that Indomitable sustained could, I think, be given a rush repair job (she was sent to Norfolk for repairs OTL, and returned to the ETO in February 1943), since it only affected the lifts and upper hull, not the engines, shafts, island, or deck; it's possible that even just restoring one lift could have allowed it to participate fielding the bulk of its normal air group. Even if not, however, the loss of 36 Fulmars and Albacores is not too much of a hit from the array of air power Cunningham and Eisenhower were able to deploy for TORCH's opening phase, let alone operations afterward.
So what we could have, and what I think we *would* see, is
Saratoga and
Wasp available to Nimitz by July - plus any
Yorktown class survivor from Midway, if there is one - plus two
Illustrious-class carriers by August, with
Ranger and the four CVE's reaching Pearl Harbor by December. Not quite a match for Kido Butai, and certainly not enough to start staging any counteroffensives, but if backed by any reasonable land-based airpower (say, especially if Yamamoto tries Operation FS after all) and good intel, a force strong enough to give battle. Especially if Yamamoto ain't expecting 'em.
Someone earlier mentioned the possibility of diverting
Massachusetts from TORCH, too. This seems suboptimal given how important a role she played in knocking out
Jean Bart and the battery at El Hank, and hardly necessary since four of the new fast battleships were already scheduled to head to Pearl that summer anyway (
North Carolina, Washington, South Dakota, Indiana) and the need is really for carriers anyway.