LONDON . I don’t know about you, but I find dinner conversations often veer in strange directions these days, like the friend telling me the other evening that the terrorists calling themselves Islamic State could easily dispatch one of their own to West Africa, make sure he contracts Ebola, then get him onto the London Underground or the Paris Metro or the New York subway, squeezed up against plenty of other folk at rush hour, and bingo!“I mean,” he said, “I can’t possibly be the first to have thought of this. It’s easy. They want to commit suicide anyway, right?”Right: We are vulnerable, less safe than we thought.

A mouthful of pasta and on he went about how the time has come to blow up the entire Middle East, it’s done for, finished; and how crazy the energy market is right now with the Saudis trying to drive down prices in order to make costly American shale oil production less viable, which in turn should ensure the United States continues to buy Saudi crude even now that it has become the world’s largest oil producer.

But of course the Russians are not happy about cheap oil, nor are the Iranians, and the bottom line is it’s chaos out there, sharks devouring one another. Nothing happens by chance, certainly not a 25 percent drop in oil prices. Somebody would pay for this plot.

Not so long ago, I struggled to remind myself, this guy was brimming over with idealism, throwing in a big investment-banking job to go to the Middle East and invest his energies in democratic change, a free press, a new order, bending my ear about how the time had come for the region and his country in particular to join the modern world. Nothing in the Arab genome condemned the region to backwardness, violence and paranoia. His belief was fervid. It was married to deeds. He walked the walk for change. I was full of admiration.

Then a shadow fell over the world: annexations, beheadings, pestilence, Syria, Gaza and the return of the Middle Eastern strongmen. Hope gave way to fever. When Canada is no longer reassuring, it’s all over.

We are vulnerable and we are fearful. That is the new zeitgeist, at least in the West. Fanaticism feeds on frustration; and frustration is widespread because life for many is not getting better. People fret.

Come to think of it, our conversation was not encrypted. How foolish, anybody could be listening in, vacuuming my friend’s dark imaginings into some data-storage depot in the American desert, to be sifted through by a bunch of spooks who could likely hack into his phone or drum up some charge of plotting against the West by having ideas about the propagation of Ebola. Even the healers are being humiliated and quarantined, punished for their generous humanity, while the humanoid big-data geeks get soda, steak and a condo in Nevada.

There were cameras and listening devices everywhere. Just look up, look around. It was a mistake to say anything within range of your phone. Lots of people were vulnerable. Anyone could hack into the software in your car, or the drip at your hospital bed, and make a mess of you.

What has happened? Why this shadow over the dinner table and such strange fears? It seems we have the remorse of Pandora. The empowering, all-opening, all-devouring technological spirit we have let slip from the box has turned into a monster, giving the killers-for-a-caliphate new powers to recruit, the dictators new means to repress, the spies new means to listen in, the fear mongers new means to spread alarm, the rich new means to get richer at the expense of the middle class, the marketers new means to numb, the tax evaders new means to evade, viruses new means to spread, devices new means to obsess, the rising powers new means to block the war-weary risen, and anxiety new means to inhabit the psyche.

Hyper-connection equals isolation after all. What a strange trick, almost funny. The crisis, Antonio Gramsci noted in the long-ago 20th century, “consists precisely in the fact that the old is dying and the new cannot be born.” Many people I talk to, and not only over dinner, have never previously felt so uneasy about the state of the world. There is something in the air, fin-de-siecle Vienna with Twitter.

Hope, of course, was the one spirit left behind in Pandora’s Box. One of the things in the air of late was a Google executive dropping to earth from the stratosphere, a fall of 135,890 feet, plummeting at speeds of up to 822 miles per hour, and all smiles after his 25-mile tumble. Technology is also liberation. It just doesn’t feel that way right now. The search is on for someone to dispel foreboding and embody, again, the hope of the world.