The USA will require a passport or other specified documentation for entry into the U.S. from Canada and from all other countries. This will affect both Americans and Canadians.
Since January 2007, a passport has been required to enter or leave the U.S. by air. The requirements for land and sea travel will go into effect no later than June 2009.
Travel registration is a free service provided by the U.S. Government to U.S. citizens who are traveling to, or living in, a foreign country.
Registration allows you to record information about your upcoming trip abroad that the Department of State can use to assist you in case of an emergency.