Suggested but not required, for now.

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Plans to require Mexicans, Canadians, and Americans to have their passports with them when they cross into and out of the United States appear to have been shelved by President Bush, at least for now. I guess he finally realized the practical and even economic consequences. Even though the plans have been put on hold, the directive to tighten the borders is still in effect. How exactly that will work is still years off. The use of background checks on new applicants for the FAST, NEXUS and SENTRI cards plus the use of biometrics are frequently being mentioned but again, that will take a while to put into place. I still have four years left on my U.S. passport despite the government's preference for the new versions.