Inefficient command structures, conflicts between Allied commanders and differing American and British military cultures all contributed to a huge missed opportunity, described by many historians as 'The Great Mistake'. On September 4, 1944, the British 11th Armoured Division entered Antwerp, capturing the docks intact with Belgian assistance. It was 85 days, however, before the first Allied cargo ship reached the docks on November 29. Some 80,000 soldiers of the German Fifteenth Army slipped across the Scheldt Estuary and escaped towards Germany along the Beveland peninsula. Had 11th Armoured Division immediately sealed off the peninsula where it joined the mainland, the Allies could have eliminated the Fifteenth Army and opened Antwerp's port much earlier, potentially allowing them to cross the Rhine and defeat Nazi Germany in 1944.
The Great Mistake: The Battle For Antwerp And The Beveland Peninsula, September 1944