Travel rules, regulations and restrictions have changed considerably in the last decade, particularly since the terrorist attacks of September 11, 2001.  US passports are in high demand since they are currently a requirement for certain types of travel.  Other types of travel do not require a US passport, though the rules will be changing again in the coming months and years.  If you are planning air travel in the near future, you're probably wondering what rules apply to you. 

The changes that have occurred in land, sea and air travel regulations have come about as the result of the Western Hemisphere Travel Initiative.  This program was launched in 2004 in response to the drafting of Intelligence Reform and Terrorism Prevention Act of 2004.  It was enacted to strengthen the security of US borders without making it prohibitive for US citizens and legitimate foreign visitors to cross American borders. 

The Western Hemisphere Travel Initiative is a joint effort between the United States, Canada, Mexico, Bermuda and the Caribbean region.  The Western Hemisphere Travel Initiative dictates a uniform standard of documentation which is required by every person wishing to enter and leave the areas which are covered by this agreement.   

The Western Hemisphere Travel Initiative has been implemented in several stages in order to give the public time to prepare for the changes.  The first stage to affect air travel was enacted in January of 2007.  The standard of required documentation for air travel has not changed since, though changes to land and sea travel have occurred in that time.  According to the Western Hemisphere Travel Initiative, all foreign air travel (i.e. airplanes leaving the United States) requires a US passport both to leave and re-enter the US.   

It is important to note that travelers are not required to carry a US passport for domestic flights.  There is no stipulation regarding domestic air travel in the Western Hemisphere Travel Initiative.  However, there is speculation by travel experts and government groups that one day a US passport may be required even for domestic flights.  This policy would fall into line with a number of other countries, particularly in Europe and the UK. These countries currently require locals and foreigners alike to present a passport for everything travel related, including domestic air travel and hotel stays. 

It is also important to note that the documentation required for air travel is stricter than the rules for travel by land and sea.  As of January 31, 2008 land and sea travel can be undertaken without a US passport.  In lieu of a US passport, travelers must present a legal form of government photo identification AND a proof of citizenship document (birth certificate or naturalization certificate.)  Air travelers have been caught in the confusion in the past few years and some have unfortunately found themselves stranded in airports because they were unaware that air travel requirements differ from other types of travel. 

The final stage of the Western Hemisphere Travel Initiative will take effect in June, 2009.  In anticipation of this, travel agents and US government officials are urging that all American citizens apply for a US passport.  A US passport is the only worldwide, universally-accepted form of travel identification.  While Americans will still be able to cross land borders without one after June of 2009, a US passport will speed up the process considerably and make for fewer delays at border crossing stations.