Why Ark Royal and the Illustrious class had complementary roles

Would an early Italian carrier have pushed Britain toward Mediterranean armored carriers sooner?

The premise is too theater-specific: Ark Royal and the Illustrious class filled complementary strike and fleet-carrier roles that Britain could use across its global commitments.

An Italian carrier would not simply have accelerated a British carrier type designed for the Mediterranean. Ark Royal was a strike carrier held for concentrated attacks, harbor strikes such as Taranto, and air defense for mobile forces. Courageous and Glorious could have served in a similar strike capacity, while Ark Royal's availability could draw attention and help an armoured carrier approach. The Illustrious class instead worked nearer the battle line with spotting aircraft, torpedo aircraft, and fighter protection. That proximity raised the likelihood of damage and made protection central to the fleet-carrier role. The comparison connects different design choices to complementary operational jobs inside one global navy.