Yup. The 9/11 hijackers were already in the US and taking domestic US flights, so the only security they had to go through was *laughs* US airport security. And at that time US airport security was subcontracted out to private security firms, many of whom were shady and hired anyone and his brother, not doing much in the way of criminal background checks. It's a crappy job, scanning millions of carry-ons of already frustrated passengers, so no one really wants that job.
While I agree with requiring a passport and US customs did catch the guy who was going from Vancouver to Seattle to blow up the Space Needle because he acted nervous, I don't think it's good for both US and Canada tourism for the border guards to intimidate everyone and ask all those bizarre questions. People are tired from flying/driving, and some people are just shy. Most people are law-abiding citizens, and it certainly can't be realistic to assume that everyone is a terrorist. How about just having more friendly customer service-type people do the passport and instant criminal check, and the customer service person directs you to the real border guards if there's something funky with your background check?
