I don't think Canada, the United States, and Mexico should standardize their rules of entry, or if they should, it's just happenstance, because we all have a little bit different interests.
What we ought to do, though, is try to ascertain, as we talked about earlier, the many safe, good, honest, hard-working folks who pose no threat to anyone. The less time people at the border and people at the airports have to spend checking my grandmother's shoes, the more time they can spend looking for bad guys. This applies to all three countries. We need to try to isolate as many people as we can in the vast, unwashed middle—right now, we don't know who they are—and put them in the good guy category. The trick is not to put them in the bad guy category unless they're bad.
To me, that's the way we address this problem.