I think one carier would have been next to useless... it would been a bomb magnet like the Bizmark or Tirpitz.
Now if they had 3 or 4 in the Med, The Germans may have held on to North Africa. A lot more supplies would have got through to Rommel. Perhaps American Carriers would have been diverted from the pacific and the war in the Pacific would have been prolonged.
Alas, it means nothing. There was a finite amount of recourses and capability. It's not just about the carriers but all the airplanes, crews, salors and support vessels.
They did the right thing by not developing carriers. They could not have sustained proper deployment or recovered from losses.
One carrier sunk represents a lot of assets on the ocean floor!
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