Churchill knew that while wars in Europe are fought on land they are won at sea. So long as England held the Channel, Hitler could huff and puff all he wanted, Nazi Germany wasn’t invading England.
Even if the RAF had lost the “Battle of Britain”, there is no way the Germans could have landed and kept supplied an invasion force. In 1940, air power had no persistence. Aircraft came, ruled the sky and whatever they were flying over, then went back to base and let the real combatants get on with it. So Germany was able to control the channel for about 4 hours a day max, then they went home and what ever was floating there then did so at the mercy of the Royal Navy.

Today the US Military has the ability to put aircraft over any place on this planet and keep them there as long as POTUS wants them to stay. Only Americans can stop America. Which is another use of NO.
This administration thinks that by using NO on ourselves, others won’t. That is delusional, of course.