Late at night, in most places I knew, there was almost no traffic and driving, a meditative activity, could cast a spell. Behind the wheel, gliding along, I was keenly aware of being an American in America, on a road that was also metaphorical, making my way through life, unhindered, developing ideas, making decisions, liberated by the flight through this darkness and silence. With less light pollution, the night sky was different, too — starrier, more daunting, more beautiful.

I have not seen roads or night skies like that for many years. As Gosse said about the ring of living beauty of the English shore, “All this is long over and done with.”

A longing for a simpler world, for a glimpse of the past, is one of the motives in travel. But the rest of the world has fared no better in terms of population pressure, and in many places it is much worse, even catastrophic. The population of Malawi 40 years ago was small and sustainable. None of us Peace Corps volunteers there at that time thought in terms of rescuing the country but only of helping to improve it. Now Malawi can’t feed itself; it’s one of the many countries that people wish to flee, renowned for being hopeless, unjustly publicized as an enormous orphanage of desperate tots, needing to be saved, devoid of pride, lost without us. The notion that a pop singer (back then it would have been Elvis) would breeze through and scoop up a child in a condescending gesture of rescue was unthinkable then.

In India a few months ago, as I was leaving my hotel in Chennai, I noticed a hotel employee shadowing me. He warned me that the sidewalks were so packed with people I would be swallowed up and stifled. He was right. And I was unable to cross the main street in Bangalore, a leafy city of under a million people in 1973 and now a hectically improvised sprawl of seven million. Mumbai’s population of nearly 20 million rivals that of São Paulo, Brazil, and Lagos, Nigeria — nightmare cities.

Travel, except in almost inaccessible places, is no longer the answer to finding solitude. And this contraction of space on a shrinking planet suggests a time, not far off, when there will be no remoteness: nowhere to become lost, nothing to be discovered, no escape, no palpable concept of distance, no peculiarity of dress — frightening thoughts for a traveler.

Yet some of the most populous countries manage to be habitable because they are societies with strict, and civilized, codes of conduct. India, China and Japan are convenient examples, but I would include many African and Middle Eastern countries, too. The vindictive stereotype of the Muslim as a xenophobe does not tally with my experience of wandering in the Muslim world, where I have been treated hospitably, welcomed by strangers as “dayf al Rahman,” a guest of the Merciful One.

We are passing through a confused period of aggression and fear, characterized by our confrontational government, the decline of diplomacy, a pugnacious foreign policy and a settled belief that the surest way to get people to tell the truth is to torture them. (And by the way, “water boarding” was a torture technique at the worst of the Khmer Rouge prisons.) It is no wonder we have begun to squint at strangers. This is a corrosive situation in a country where more and more people, most of them strangers, are a feature of daily life. Americans as a people I believe to be easygoing, compassionate, not looking for a fight. But surely I am not the only one who has noticed that we are ruder, more offhand, readier to take offense, a nation of shouters and blamers.

Yes, it is just silly and fogeyish to yearn for that simpler and smaller world of the past. But one could ask for the past’s better manners, the instinctive decorum that has served to mitigate conflict. One of the lessons of travel is that, though half the world is wearing T-shirts and sneakers, they manage to live in overpopulated cities because they have not abandoned their traditional modes of politeness. These grace notes, which make traveling in crowded countries bearable, are a lesson to us in a mobbed and jostling world.