RAF interception over Dunkirk and the home-defence reserve

The discussion answers the criticism that the RAF was absent from Dunkirk by explaining that fighters tried to intercept German aircraft before they reached the beaches and ships. Interceptions were often unsuccessful, so troops under attack could reasonably fail to see the defensive effort taking place elsewhere. The absence of fighters directly overhead therefore did not prove that no protective missions were being flown. Fighter Command also had to preserve strength against the feared attack on Britain that soon became the Battle of Britain. The result was an air-defence problem shaped by incomplete interception, competing priorities, and the difference between activity in the air and what observers on the ground could see.