I don't know why BBC America does not air classic Who. Maybe they do not have the rights or the main network in Britain only wants to showcase the modern material who can tell?
They did show it ever so briefly when the channel was young (I think before nuWho though I can't explicitly remember). It would come on weekend mornings and only showed the fourth Doctor while it ran.
I don't know if it's by mandate or what I think is more likely that it just didn't do that well ratings-wise.
Thabks for your honest reply, I figure the new series Doctors would be the bigger draw as it is the more recent adventures of the Time Lord and his companions.
Loving that avatar of Karen and Matt btw!