Canadians already get CNN and AJ. Cable channels do not broadcast, they are a closed feed, and perhaps may not be forced to meet the same requirements as network broadcasts.
I am not sure how Canadian law differentiates, but I do know that the FCC has different sets of guidelines for both.
It's a violation of both GATT and NAFTA for the Canadian government to discriminate against American companies. The US should take them in front of the WTO.