the closest thing the US ever got to NB was during the 80's when viz translated a part of the Kamui saga...
i really wish more old manga would be translated. stuff like ashita no joe, kintaro of the graveyard, tetsujin-28, gaki deka... what really frustrates me is that some of the most popular "classic" artists will probably never be imported into the US. guys like sampei shirato, fujio akatsuka, kazuo umezu, go nagai, leiji matsumoto...