Originally Posted by
fastair
The FAA and the TSA (as well as the airlines) think so. Most of your post I agree with, but if you believe they aren't many regulators responsible for security would tell you you are wrong.
So settle it for us once and for all
a) passports are checked because its the rule to Canada
b) passports are checked because the airline doesnt want to pay fines/costs of return
c) passports are checked because "places like Japan and Hong Kong never had thousands of citizens die in a terrorist attack, so their security protocols are lax."