us visa restrictions

Aliens entering the United States must obtain a visa from one of the U.S. diplomatic missions. Visitors may be exempt if they are citizens of one of the visa-exempt or Visa Waiver Program countries.
The same rules apply for travel to all U.S. states, Washington, D.C., Puerto Rico and the U.S. Virgin Islands, as well as to Guam and the Northern Mariana Islands with additional waivers, while similar but separate rules apply to American Samoa.

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