that means destroying the luftwaffe, but only if the luftwaffe comes out to fight. they will fight over berlin, but why is that? student: hitler is there. it is the center of german culture. bombedn't let it get over and over again. prof. miller: it is a prestige target. hitler can't allow something like that to happen. the price of nationalism kills him in this case. they had the best fighter defenses in the reich around berlin it is an economic powerhouse, but still. if you mount 1000 bomber raids on berlin and population of berlin sees luftwaffe isn't enough and the flat guns are flak guns are firing constantly -- a dictatorship does depend somewhat on popular opinion. they had spies going to nazi meetings. this is -- the bombings are starting to erode confidence in the fuhrer. they dropped a lot of ordinance on berlin, a lot. in some raids, 17,000 bombs. they are there. when heerman full me was a kid, i knew the first time they hit berlin, and they hit it, i knew that if they can do it once, they will do it again and again until there is no berlin. that is exact

and among the barely 3,000 airmen hoconfronted the nazi luftwaffe as it tried to soften britain up for a planned invasion were a small, little-nope, and actually illegal contingent of americans. and in the anniversary fly-pass, the largest gathering of world war ii aircraft since the war was this spitfire, now owned by the historic flight charity in seattle, and flown to honor the americans by john sessions. >> it was felony in the united states under the neutrality act to fight for the british at that point in time. so most of the -- >> reporter: because the u.s. was officially neutral. somewhere between nine and 11 americans joined the battle. nobody's sure because some hid their identities pretending to be canadians. >> some of them were only identified decades later through entries in squadron books with nicknames like "tex." you know. >> reporter: tex from canada. >> they were officially canadians. >> reporter: billy fiske, though, was american through and through, a well-known olympic gold medalist who joined a high-profile squadron, he died during the battle, perhaps the first a