BLTs, on the other hand, are nearly impossible to recreate properly outside of the States. For one thing, American bacon is very different from the stuff they call bacon elsewhere. And some parts of the world don't even have anything that they call bacon. For another, no one has quite the right kind of sliced white bread. I'm not saying that sliced bread is the greatest thing since, well, sliced bread, but it's just different. The sliced bread you can buy abroad is just... wrong, somehow. Not the right texture or taste, I can't explain it, but it's wrong. As for non-sliced bread, a French baguette or a Swiss Zopf are both lovely, and in many ways superior to plain, sliced, pre-packaged white bread, but not for a proper BLT.*
Same goes for hamburgers. No one outside of the States -- person or restaurant --seems to be able to make a proper burger. The buns are wrong, the meat doesn't taste quite right, and it just doesn't work the same way. It baffled and frustrated me while I was away, but now that I'm back, I don't eat them that much, and when I do, it's sometimes in a different form, like the Luther burger.
Now that I think about it, peanut butter and jelly is hard to get right outside of the U.S., as well. There's the bread thing, and then there's the fact that peanut butter is a very American product (it can be hard to find a good substitute brand once you're abroad), and even if you find good peanut butter (or import it in your luggage), not a lot of places have that clear, wobbly grape jelly that is used in 90% of PB&J (and doesn't really have any other use at all).
Deli sandwiches? The rest of the world has excellent meats and cheeses, but they aren't really sold in sandwich format. Pre-made sandwiches in Switzerland usually consist of a roll, butter, a slice of pickle, and a few slices of salami. Where's the tomato? Where's the lettuce? Where's the cheese? Basically, where's the sandwich part of the sandwich?
So on a scale of 1 to American, I'd say that sandwiches rank much higher than apple pie or baseball.
* (I rediscovered BLTs a few months ago and have been eating them almost obsessively since then. I've settled on farmer's market heirloom tomatoes, Trader Joe's buttermilk bread, red lettuce, and Trader Joe's bacon as the best combination. Plus mayo, and if you're feeling unconventional, ketchup and a fried egg. Heaven and a heart attack, both at once.)