This market predicts when a nuclear weapon will be used aggressively. Resolution criteria:

Qualifies as aggressive use:

• Use of any nuclear weapon (including tactical) against another nation

• Nuclear detonations caused by non-state actors or unknown perpetrators

• Accidental nuke uses that impact outside the initiating nation's borders

• Attempted nuclear attacks that are intercepted by defense systems

Does NOT qualify:

• Nuclear testing

• Weapons of mass destruction that do not primarily depend on fission or fusion (e.g. conventional explosives that scatter radioactive materials around their target)

• Peaceful nuclear uses (mining, asteroid deflection, etc.)

• Accidents contained within a nation's own borders

Sources for verification:

• Any two large news agencies comparable to AP, Reuters, Al-Jazeera.

The AI assistant also recommended:

• Arms Control Association

• Brookings