Good stuff CaptainCrunch! Good point on Dunkirk by the way.
I should also note that the Battle of Britain marks the first time the Nazis were defeated in a major campaign. This strengthened Britains resolve because now the Nazis were no longer viewed as this unstoppable machine. It also renewed the Americans belief that the war had hope, and that the Britain did not fall.
I find WW2 stuff facinating. Can you imagine what would have happened if the allies had lost? We would all be eating sushi, watching anime, and driving german cars...
...wait