All scenarios / Human-made
World War III
Sequels are rarely better than the original.
What it is
World War III means a direct, sustained war between great powers, such as the US and its allies against Russia, China or both, fought on several continents. It overlaps heavily with nuclear war, but the two aren't identical. A global conventional war could still wreck supply chains, energy markets and food systems for billions of people without a single warhead going off.
Why it ranks where it does
World War III ranks second because experts are unusually worried about it right now. In the UN's latest Global Risk Report, 36% of about 1,300 experts said they expect a large-scale war within a year, and 76% said within seven years. Russian hybrid attacks on infrastructure in Eastern Europe have escalated since August, and the Iran war has drawn in several regional powers. Our score moves with live prediction-market odds on a NATO–Russia clash, a China–Taiwan clash and a US invasion of Iran.
Evidence on the board
- UN Global Risk Report: 36% of 1,300 experts expect a large-scale war within a year, 76% within seven. Ground News ↗
- Russian hybrid attacks on Eastern European infrastructure have escalated since August. ZeroFox ↗
What the experts say
No major-power war has broken out since 1945, and historians often credit nuclear deterrence and economic interdependence for that. Both still apply, which is why our number stays well below a coin flip. The worry is that the number of active flashpoints is unusually high and that crisis communication channels between the powers have weakened.
What would move the number
Up
- Direct exchange of fire between NATO and Russian forces
- A Chinese blockade or invasion of Taiwan
- Formal military alliances being activated, such as NATO's Article 5
Down
- Negotiated ceasefires in Ukraine or the Middle East
- Restored military hotlines between Washington, Moscow and Beijing
- Falling Polymarket odds on the precursor events
Live signals we track
The baseline above is set from the evidence as of October 13, 2026. On the live board, your browser adjusts it in real time using these feeds. Chatter can only nudge a score in proportion to its evidence, so attention alone can't make an unlikely scenario look likely.
- Prediction market: NATO × Russia military clash in 2026, 23.5% at snapshot Polymarket ↗
- Prediction market: China × Taiwan military clash before 2027, 4.4% at snapshot Polymarket ↗
- Prediction market: US invades Iran before 2027, 17.5% at snapshot Polymarket ↗
- Public attention: daily Wikipedia pageviews for World War III
- Online chatter: Hacker News stories mentioning "world war" this week vs. the prior eight weeks
Sources
- Wikipedia: World War III
https://en.wikipedia.org/wiki/World_War_III - Ground News
https://ground.news/article/world-fears-major-war-more-than-any-other-global-risk-un-survey-finds - ZeroFox
https://www.zerofox.com/intelligence/monthly-geopolitical-report-october-2026/ - Polymarket: NATO × Russia military clash in 2026
https://polymarket.com/event/nato-x-russia-military-clash-in-2025 - Polymarket: China × Taiwan military clash before 2027
https://polymarket.com/event/china-x-taiwan-military-clash-before-2027 - Polymarket: US invades Iran before 2027
https://polymarket.com/event/will-the-us-invade-iran-before-2027
Baseline scores are an editorial threat index from 0 to 100 that combines current reporting with published expert estimates. They're meant for comparing risks, not as actuarial forecasts. See how the numbers work.