Surface raiders created an escort dilemma

Destroyers, corvettes, frigates, trawlers, and later escort carriers gave convoys strong anti-submarine protection but little answer to Scharnhorst and Gneisenau. Britain used older battleships from Halifax when the surface threat was high, but its capital ships also had Mediterranean and global commitments. A sustained German presence could force fewer and larger convoys, pause sailings, or consume battleships as escorts. Each choice carried operational and political costs. The raiders' greatest leverage lay in forcing those choices even before they fired on a merchant ship.