Mediterranean containment and French rail logistics

The strategic geography weakened the case for relying on battleships to defeat France. French supplies could arrive at Atlantic ports and travel south by rail rather than pass through waters exposed to Italian attack. The Royal Navy at Gibraltar also made a surface breakout from the Mediterranean highly unlikely, even if submarines might sometimes pass through. Those constraints strengthened the case for a larger cruiser, destroyer, and escort force suited to operations Italy could sustain inside the Mediterranean. British strategy also depended on France remaining able to absorb much of the land fighting in a European war. The Anglo-French alliance is presented as practical realpolitik rather than friendship, giving Britain another reason to keep France functioning.