dr. freidman. james hornfisher in "neptune's inferno" talked about the exchange with an role -- when he trained at harvard. [indiscernible] were there any exchange programs where they came to the united states? norman: there was not an exchange program. it was naval attache. that is how we got to go around. yamamoto -- no, you do not -- want your students to watch you playing these kinds of games. it was not their business. >> because i was wondering, in "neptune's inferno," he talked about the japanese superiority in night fighting, like you were saying, but there were -- were there exchange programs or any other, what attaches studies any intelligence or anything? norman: no. no one was ever allowed in. as far as going to japan went, their security was terrific. they were very good at making sure foreigners stayed out of business. if you think about russians -- and the russians worked really hard at it. you only see exchange programs later when the war college is no longer such a sensitive thing.