Starting tomorrow, 1/23/2007, "...United States citizens, including children, returning [home] by air from any country [including Jamaica] in the Western Hemisphere will have to present a passport.

In another change, citizens of Canada and Bermuda traveling to the United States by air will also have to show passports to enter the country. Previously, they too could use driver’s licenses and birth documents.

The new measure applies only to air travelers. Officials in the Department of Homeland Security said they expected to roll out the same restrictions for passengers arriving by land and sea by Jan. 1, 2008."

http://www.nytimes.com/2007/01/22/us/22passport.html
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