Why Mediterranean refuelling favored secure ports

Aircraft range compressed the Mediterranean and exposed slow, valuable supply vessels. Protecting tankers could consume escorts and air cover also needed by carriers and battleships, as the scale of the Malta convoys demonstrated. Underway refuelling remained possible, especially at the eastern and western ends, but the central sea offered a poor balance of risk and reward. Malta was essential as a base, yet its vulnerability to air attack made it an unsuitable permanent fleet concentration point.