I am guilty of using "World War III" as shorthand for "War Between the Great Western Powers". I plan to be more precise with my language in the future.


The worst likely outcome of the Ukraine-Russia war is a total nuclear exchange between Russia and NATO. Assuming Russia's nukes function as intended, the only countries likely to be nuked are NATO, Russia and a few allies.

Europe (including western Russia) has a population of 751 million people. The USA plus Canada has a population of 372 million. That's a total of only 1.1 billion people. If we add Ukraine and Belarus the total rounds up to 1.2 billion people.[1]

The world population is 7.9 billion people. 15% of the world population isn't a "world war". If it was, a war between India (1.4 billion) and Pakistan (0.2 billion) would be a world war because they have 20% of the world population—and that's not even counting Bangladesh.

It's not a world war if China, India, Indonesia, Pakistan, Brazil, Nigeria, Bangladesh, Mexico, Japan, Ethiopia, the Phillipines, Egypt and Vietnam aren't fighting. I predict that none of the above countries will engage in direct hostilities that spiral out of the present Ukraine-Russia war.

World War II was a real "world war".

Nuclear war between Russia and NATO would unleash suffering at an unprecedented scale. But it wouldn't (by itself) constitute a world war. Most of Asia, Latin America, Africa—none of them are likely to be directly involved.

Would China take the opportunity to invade Taiwan? Maybe. If the USA (after getting nuked by Russia) defended Taiwan then, yes, I think we could call it a world war because it would include the world's three major powers (NATO, China and Russia). But a European war, even it includes the USA, is not a world war. It wouldn't even include all five permanent members of the UN Security Council.

This isn't to say non-white people would come out unscathed. Homo sapiens would be facing nuclear winter. The global economy would be in ruins. But most human cities would not be the target of nuclear strikes.


  1. My numbers fail to count Asian Russia but they also include (when they shouldn't) non-NATO European states. Even if we counted every Russian twice, the total would still come out to less than the population of India plus Pakistan. ↩︎

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Is this post about anything more than semantics? If yes, why does it matter?

It helped me realize that, if you place a high premium on avoiding the direct fallout (metaphorical or literal) of this conflict's worst-plausible-case scenario, it might be a good idea to spend the next few months holidaying and/or remote-working in an uninvolved nation.

Those were my exact thoughts after publishing my post.

It's about perspective. When I say "world war" I think world war. Not "regional war involving Europe and the USA". Those are different things.

Clarifying such differences helps me grasp the importance (in units of human suffering) of the Indian subcontinent. I didn't realize how much more important India is (compared to the entire Western world) in quality-adjusted life years.

It matters because semantics matter.  The media in general has been quite shrill about "world war III", using it to acquire eyeballs and ad revenue.  While it IMO doesn't quite rise to being blatantly false, it's still misinformation, or at least information distortion.

I tend to use "world war III" as shorthand for "big nuclear powers committed enough to actually launch their mutually-assured destruction mechanisms".   I assign fairly small probability to this being small enough for any significant portion of the world to escape chaos and destruction.  Even if many survive, there will be so much disruption that "local violence" is common.

Additionally, I think it's likely that big non-Western powers would use the opportunity to perform violence on their neighbors, making it a true world-wide war zone, even if it's not technically the "same" war officially.

It is useful to have a shorthand for "big nuclear powers committed enough to actually launch their mutually-assured destruction mechanisms". "Nuclear war" doesn't do the job because it requires the launching of nukes (not just the possibility) and because it includes small-scale one-sided nuclear strikes (such as North Korea vs South Korea).

Additionally, I think it's likely that big non-Western powers would use the opportunity to perform violence on their neighbors, making it a true world-wide war zone, even if it's not technically the "same" war officially.

Yup. I think such an eventuality ought constitute a state of "world war". After all, Japan and the USSR had a non-aggression pact until 1945.

It's not a world war if China, India, Indonesia, Pakistan, Brazil, Nigeria, Bangladesh, Mexico, Japan, Ethiopia, the Phillipines, Egypt and Vietnam aren't fighting.

As a nitpick, see the Kuril Islands and Japan recently calling them "ancestral territories"

This seems to be based on your own definition of  World War.  Instead of population, you could have used the GDP of the countries involved, the number of countries or even the total surface. I do agree that a war between Pakistan and India wouldn't be a World War,  which suggests in fact that the definition you are using here does not really capture what a World War is.

The GDP definition makes sense. It's certainly reasonable. It we use GDP as the definition then Russia's involvement doesn't matter (except to the extent it nukes NATO) because Russia's GDP is a rounding error compared to the GDP of the USA and its European allies.

I suspect that massive destabilization following the precipitous fall of most of the great powers (NATO + Russia at the least) would result in war on every continent (sans Antarctica). If Asian countries don't get nuked in this scenario like you suppose, I think it's quite plausible general war in Asia would follow shortly as the surviving greatest powers jockey for dominance. If we posit the complete collapse of U.S. power projection in the Pacific, surely China is best positioned to fill the void, and I don't think it's clear where they'd draw the new lines.

The concept of "world war" doesn't need to mean "most of the world's population is involved in this war," not when nuclear weapons are at stake. A nuclear exchange between NATO and Russia is world-shifting in a way that a nuclear exchange between Pakistan and India is not. Calling nuclear war between major Western powers (which will almost certainly have devastating economic and physical effects on the entire world) a "world war" seems perfectly reasonable at that point, even if most of the world is not directly involved.

A point worth considering is the difference between agency of the belligerents vs. the consequences of the war. Even in WWII, the consequences of the war were mostly local for the belligerents; France and Germany, Russia, Japan and China were all much more affected by the destruction of their cities and fields than they were anything that happened with international trade or similar.

The nuclear winter scenario is one that affects all countries similarly, insofar as nuclear winter is the worst thing for the neutrals and also the worst thing for the belligerents, even granting multiple nuclear strikes. Depending on how a person ranks swift incineration vs inevitable starvation, being a belligerent might even be less bad.

I'm not sure how to weight it, but a point worth observing from the WW2 comparison is the absence of colonial possessions and the presence of diplomacy or opportunism to bring additional countries into the war on either side. For example, British India resulted in modern Bangladesh, India, and Pakistan all being involved in the war based on the European theatre of the conflict, as opposed to the much closer and materially-more-relevant China/Japan theatre. An example where the conflict could easily extend is that both Russia and the United States maintain military assets in different host countries. Examples: Syria is host to Russia's assets which operate in the Mediterranean, which is NATO's underbelly; Japan and Korea host American assets which can reach Russian territory.

Regarding China, which is the largest x-factor in terms of both outcome and this criteria: it seems to me that the only thing preventing their involvement through a similar string of diplomatic escalations is the judgment of the Chinese government. Among other things, it becomes hugely in Russia's interest to bring them into the war, in a manner analogous to it being in Britain's interests to bring the US into WWII.

There are too many vectors for a NATO/Russia conflict in Ukraine to extend throughout the rest of Asia at least for me view this is as just a European war by default.

Does cyberwar count? Including social manipulation on social media on a global scale?

Nope. Social media manipulation is propaganda. Propaganda is a form of speech. Free speech does not constitute "war". Neither does espionage. (Most cyberattacks are a form of espionage.)

What if, hypothetically speaking, manipulation on social media causes measurably increased rates of suicide, drug consumption, terrorist attacks, etc.?

Propaganda that increases suicide and drug consumption does not constitute a war. With terrorist attacks, it depends on the details.

What about taking down enemy websites, their internet, their power supplies etc.?

Hacking individual websites does not constitute a war. Using cyberattacks to disrupt Internet and electricity might. It's uncharted territory.

Hey uhhhhhh is there a map of the world showing likely nuclear war targets and expected fallout radius? Like Nukemap. Asking for, uhhhh, a friend in a maybe-risky area.