----- Original Message -----
From: "Tim Gilbert" <tgilbert@...>

The rule about Canadian cars was not an AAR one, but could be enforced
by US customs. If a Canadian car was reloaded and routed via an
all-American route, US Customs could deem that customs duty had to be
paid on the Canadian car. Canadian customs could extract the same for
an American car having all-Canadian routing.

----- Original Message -----

There is a similar principle with airlines called cabotage which holds that a foreign airline cannot transport passengers between two US locations - they can only take people into or out of the country.

KL