Here’s an interesting statistic: By late 2011, 109.8 million people held U.S. passports. That’s 35 percent of U.S. citizens, far less than citizens of many other countries, but in this country, that's a record, not only in numbers of passports but in percentages of U.S. citizens who hold them.
The number of Americans who have passports has been increasing steadily for at least the last decade. In 2000, only 18.5 percent of U.S. citizens held passports. By the end of 2005, 24 percent did.
One reason: road trips. Most travel out of the country is to places you can drive to. In 2010, 60.3 million U.S. residents traveled outside the country, according to the U.S. Department of Commerce. Just over half stayed in North America: Mexico (20 million) and Canada (11.7 million).
Until a few years ago, U.S. citizens didn’t need a passport to visit Canada or Mexico. But in order to tighten controls over who entered the U.S., the government started requiring U.S. citizens to have passports for travel to (or more specifically, return from) Mexico, Canada and the Caribbean/Bermuda in 2007.
As a result, the number of passports issued shot up in 2007, to a record 18.3 million. Although the number has dropped since then, the U.S. has issued more passports every year since then than it did before 2007.
By the way, the third most popular country for U.S. citizens last year was the United Kingdom, with 2.4 million visitors – far less than Canada or Mexico. Following Great Britain, with about 1.8 million U.S. visitors each, were France, Italy and the Dominican Republic, with its high concentration of all-inclusive resorts.