I am thinking of renewing my passport and travelling again to the USA....

That number will increase now that Americans need a passport to go to Canada, Mexico & the Caribbean.  

I absolutely, vehemently agree that too few Americans travel abroad, and attribute our currently messed up culture to this fact.

But there does seem to be an implied sense that "abroad" means "Europe".  A lot of Americans live near the Mexican and Canadian borders and routinely cross them.  Then there are two big f-ing oceans on other side of us which making getting to other countries a small hassle.  There are not 44 other countries on our continent.  We're a bit isolated, geographically.

So there are a lot of factors preventing travel.  And now that we're all meant to be flying less for carbon reasons, I'm not sure what the answer is.

"Pretending that you already know the answer when you don't is not actually very helpful." ~Migeru.

That is now changing due to the new requirement to have a passport to return to the US from Canada or Mexico through a land border.

You don't need a passport to travel within the Schengen Area, so maybe in 30 years many Europeans won't have a passport either. There is simply no useful comparison to make there.

Oye, vatos, dees English sink todos mi ships, chinga sus madres, so escuche: el fleet es ahora refloated, OK? — The War Nerd

To be fair, what do many people (esp families with kids) do on vacations? Visit family, go camping or the beach or parks. Go to amusement parks. And so forth. The United States is huge and has all of that here. It is not surprising large numbers of people (again, esp families) choose to go on cheaper (and closer) vacations. And then when you take into account that fact that tens of millions of americans never go on vacation, it is not surprising that so few of us have passports.

I myself did not have one until I needed one for a work business trip. Before that, I didn't go on vacations (family not even middle class really and no vacation time) and I definitely couldn't afford to fly hardly anywhere, much less outside the country. It comes in handy now when I have the leisure time and the money. Vacations in my family (such as they were) were driving to visit relatives or go camping. And even that usually for less than a week.

Some data here:

http://tinet.ita.doc.gov/tinews/archive/tinews2007/20070808_travel.html

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