The U.S. Card That Lets Some Mexican Citizens Skip the Passport at the Border — Within Strict Limits

SAN DIEGO, CA - NOVEMBER 14: A U.S. Customs and Border Protection officer checks the identification of a person crossing from Mexico into the United States at the San Ysidro port of entry on November 14, 2013 in San Diego, California. San Ysidro is the busiest port of entry into the United States, with some 90,000 people passing daily between Tijuana and San Diego. (Credit: Photo by John Moore/Getty Images)

MIAMI — A travel document nearly three decades old is making the rounds again on Spanish-language social media and news sites, often framed as a brand-new way to enter the United States "automatically," with no passport or visa required. The card is real. The privilege is real. But the version circulating online leaves out most of the fine print.

What the Card Actually Is