My point with the stupid questions is to illustrate the fact that there are no sure ways of detecting a potential terror threat based on the answers given by a slightly irretated person. You have no idea of the events leading up to the border crossing which would impact ones behavior or tollerance to stupid random questions.
In your post you gave the impression that these guys were trained to a degree where they could read peoples body language and be able to tell who is a potential terrorist or smuggler. I think you insulted Criminal psycologist everwhere when you mentioned them in a coversation about the level of training these border guards are subjected to.
Take a look at the story about the underwear bomb that did not go off. Sufficient warning was given to warrant that traveller not to be allowed to go the the STates. Unlike this situation where someone is going to an outlet mall and does not know exactly what stores he will be going to.
Sure the guy was a dick and could have conducted himself better, but did it really have to get to the point of all the bullshit that took place.
The law is clear in alot of cases but does not stop overzelous assholes from abusing their authority and venturing on the otherside of it by making up bullshit reasons to detain someone or by manipulating that grey area for their own purposes.
This is all up to the individual asshole at the booth and how well his day has been so far.
it is all so up to the individual assshole crossing the border and dealing with said asshole at the booth. When you come across 2 such assholes at the same time things will escalate to where they did in this case.
The trained assholes should also exercise some level of professionalism and be able to tell if this guy was a credible threat or just some average ass letting off some steam.
the questions he asked, while could be deemed as pushing his luck was not in a disrespectfull manner but that of someone who has rights.
This can all be summed up in the words Power Trip.
Where did you order the Lip for your car?
I think it actually looks better having the lip over the M-bumper but thats another topic of discussion.