Originally Posted by cargoship
what are the chances that the US & Canada having a border arrangement like Schengen? (removal of the longest undefended border in the world)
To be fair, I don't believe that the Schengen Agreement sought to remove jurisdictional boundaries, but rather the checkpoints that were installed to police them.
That being said, the chance of a similar pact between the US and Canada is essentially nil at this point in time. The US vastly outmaches Canada in terms of wealth and power, and would simply not want its internal policies (security, immigration) mandated by a county it views with some degree of mistrust. I think that the US would welcome a system which expedites border crossings for registered individuals, but I'm not sure that many Canadians would wish to have personal data held/accessed by a foreign government.