It was unthinkable by most people at the start of the Twentieth Century. That's the sense in which I meant it.

Sez who? Scientific American ran an article on bullet trains 150 years ago. "Unthinkable" is a hyperbolic term used when one wants to dismiss all debate. Nope. Not lettin' ya.

I was born in one country, I lived for several years in another country, and now I live in yet another country.

The same was true for Benjamin Franklin. Hell, son, for someone born in Serbia in 1919 the same is true without the dude having to move houses! Which would be unique except for the fact that "country" is a modern term anyway and duchies in Germany used to change hands every ten years or so.

Before the era of mass communication, few people had a clue of what it meant to live in a different country or even a different city

So nobody had an imagination prior to the invention of television? As I recall, more people read James Fenimore Cooper's Leatherstocking tales than read Victor Hugo... and in more languages.

What was that thing about unfounded assertions? I travel a lot, I live in a country that's not my native one, and I'm not American.

Been to the Empty Quarter?

No?

Then it's a "founded assertion."

I was referring to how other people (everyone) can communicate with anyone else

My grandparents grew up without telephones. They adapted just fine.

Few people could imagine what it meant to live in a different social class, or to lead a different kind of life.

Say it again. It will remain just as false.

Throughout the Twentieth Century governments have fallen, the rights of women and minorities have gained more prominence, and several other aspects of everyday life have been revolutionized in ways that have only been made possible by an increase in the possibilities of communication.

I'm going to let you have this one, not because I agree, but because it's more important to get you back on track - so what? How does this "average person" that you insist you are not care a whit about the methodology employed to topple Mossadegh?

Now let's get to your examples:

Religious beliefs and practices don't make any sense in light of the current scientific progress, but many people still think they do.

Has been true since Galileo at least.

Additionally, many people still believe that an ethical behavior can only stem from religious beliefs, but that's false, too.

Has been true since Sargon of Akkad or earlier.

Patriotism and excessive nationalism don't make sense either, and at the very least they need to be revisited.

'K, here's where you show your ass and demonstrate that you read a book about the 20th century with no understanding of the context of the 19th and earlier centuries. "Nationalism" was a product of The Enlightenment. Germany has been a "country" since 1871. Italy ceased to be a bunch of warring nation-states in the 1860s. As an "OMG CHANGE" example, "nationalism" is a recent adaptation.

The idea, that many have, that there is a nearly-perfect form of government and that form is a democratic republic is well-intentioned but naive.

I was unaware that the world had adopted democracy, and further unaware that we've had to "adapt" to it. I like to quote Churchill on this one - "Democracy is the worst form of government except for every other one."

For millennia the world hasn't changed much, and there were just a handful of forms of government to choose from.

This is a bizarrely ignorant statement. I'm gonna say the burden of proof is on you.

Now none of them suits our society,

Every form of government suited every society it had or it was replaced by revolution. QED.

No, it's dictated by their parents and grandparents – by people who managed to adapt to the TV and the remote control, but not quite to the Internet.

Whatever, dude. Obama's got a Blackberry.

Until a few years ago, George W. Bush was one of the most important men in the world in terms of the power he held; would you say that his mentality is adapted to the realities of our present time? I don't think so.

Are you trying to argue that if GWB had Facebook the world would be a better place? 'cuz I'd like to see that.

* * *

Look. I responded because you clearly had a lot of despair in your post. Based on your response, you clearly have a lot of affection for that despair. Fine. Keep it. Just allow me to point out that when you insist on a perspective against all evidence to the contrary, you are - wait for it -

...failing to adapt.

Good day.