Globalism is in retreat and world leaders don’t understand that they are being forced by circumstances to prune it back. When the Biden administration announced that it is working on a plan that would require all foreign visitors to the United States to prove that they are vaccinated for COVID-19, it was yet another sign that the supposedly inexorable march toward greater and greater integration of global society is being reversed.

Globalism is a word used to mean many things. Let me offer a definition for what I mean from a piece I wrote in 2016:

I define globalism as the management of worldwide economic activity and growth by large multi-national corporations which have no particular allegiance to any one country or people. Our belief has been that this arrangement is the most rational and efficient. Therefore, trade deals which bring down barriers both to international trade and to the movement of capital and technology across borders are believed to encourage global economic growth. That growth supposedly will ultimately lift the world’s poor into the middle class and enrich everyone else while doing it.

I should add that a chief feature of this world is its extreme connectivity both physically through air travel and shipping and electronically through the internet. That connectivity promotes worldwide understanding, communication and trade. It also creates serious vulnerabilities and possibilities for harm to individuals and organizations.

A piece co-authored by Nassim Nicholas Taleb, famed student of risk and author of The Black Swan, lays out the case for “pruning contact networks” and “the necessity of a precautionary approach to current and potential pandemic outbreaks that must include constraining mobility patterns in the early stages of an outbreak, especially when little is known about the true parameters of the pathogen.”

The vaccine requirement for entry into the United States being contemplated by the Biden administration is an admission that our worldwide connectivity has become not only dangerous, but a lethal threat. It’s unknown whether such a requirement will be temporary or permanent. But there are complications ahead for this type of restriction.

First, there is the problem of what counts as vaccinated. As a colleague of mine often points out, there is no such thing as “the vaccine.” There are many. And, there are many more new vaccines on the way. The World Health Organization stated that as of December 2020 there were 200 vaccine candidates and 52 in human trials. Each vaccine has different characteristics and different levels of effectiveness against the many variants of the original COVID-19 virus. Which vaccines will be on the list used by the United States? Will those getting a vaccine not listed be barred from entering?

Second, boosters are already being approved for vaccines which are still being given under emergency authorizations themselves. The immunity conferred by COVID-19 vaccines appears to be relatively short-lived. Since immunity conferred by vaccines declines over short time spans, what standard will the United States use? In other words, how recent will your vaccination or booster shot have to be?

Third, as more variants develop, some may evade the protections offered by vaccines altogether. How feasible will it be to revaccinate billions of people every time this happens?

Fourth, since it is already known that vaccinated people can be infected in large numbers by variants, how effective can vaccine passports be in stemming the spread of the various versions of COVID-19—which is the whole reason for the passport program in the first place?

My guess is that the U.S. vaccination requirement will ultimately become unworkable. Nature’s wily ways care nothing about the requisites of smoothly functioning global human systems. But it’s hard to imagine world governments giving up a high level connectivity under any circumstances. That means they are risking ruin under a scenario in which a much more dangerous virus makes its way across the world.

To quote Taleb again: “With increasing transportation we are close to a transition to conditions in which extinction becomes certain both because of rapid spread and because of the selective dominance of increasingly worse pathogens.”

Contemplate that for a moment: “extinction becomes certain.” What Taleb is saying is that the global system we have built is subjecting the human population to the possibility of a wipe-out if we expose ourselves without restriction to novel pathogens worldwide. I have used the analogy of Russian roulette before. But it is worth repeating: If you play Russian roulette with a hypothetical gun with a million chambers, only one of which has a bullet in it, you will probably survive if you pull the trigger once or twice. But if you pull the trigger one million times, you will almost certainly perish.

Humans are being exposed to novel viruses every day around the world, perhaps millions of them. Almost all of those viruses have little or no effect. But it only takes one lethal and easily spread microbe to threaten the entire human population now.

It is hard to imagine our world becoming less and less connected over time as a way to mitigate the threat of novel viruses. Rather, it seems more likely that we will not heed Taleb’s call for a precautionary approach to worldwide travel. Instead, we will continue to our connected ways until something—possibly a high-lethality virus—forces us to stop.

Graphic:  Map of global passenger air routes (2013). Josullivan.59. Via Wikimedia Commons https://commons.wikimedia.org/wiki/File:World_airline_routes.png