No kidding. Volunteering that he was in Al Qaeda territory... to take pictures of plants. Saying he's a nihilist. Suggesting that the levees in New Orleans might break again while he's visiting. Having Jewish ancestry, but denying being Jewish because not religious.
Also appears he was also traveling alone to many of these places, without any business reason. Entering the US through Canada without having business in Canada sounds like somebody trying to come in a back door, and being nervous to boot.
Even from this one side of the story I'd say the border patrol did their job just fine. I wouldn't have let him into the country in that story.