U.S. to tighten border controls

Now, Americans do not need to show a passport when they come back U.S. from Canada or Mexico. However, Americans will need to show a passport after 2008, because U.S. government thinks U.S. border regulations should be stricter for protecting from terrorism.
I think this regulation can be little success. But, U.S. government cannot prevent that terrorists enter the U.S.

By Masaki