From https://metaculus.com//questions/15537/new-nuclear-armed-state-by-2030/

Since the dawn of the nuclear age, the number of nuclear-armed states has slowly increased, with nine countries currently possessing nuclear weapons. Nuclear nonproliferation efforts, such as the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), have played a crucial role in preventing the further spread of nuclear weapons. However, concerns persist about the potential for additional countries to pursue nuclear weapons capabilities, either secretly or openly, which could destabilize regional and global security.

The emergence of a new nuclear-armed state could have significant implications for international security, potentially triggering arms races or geopolitical realignments. It is therefore important to assess the likelihood of a new country successfully developing and testing a nuclear weapon by 2030, taking into account both announced and unannounced tests.

Will a new nuclear-armed state emerge before 2030?

This question will resolve as Yes if, before January 1, 2030, credible evidence becomes available that a country not currently possessing nuclear weapons has successfully developed and tested a nuclear weapon. The current nuclear-armed states are the United States, Russia, the United Kingdom, France, China, India, Pakistan, Israel, and North Korea.

This evidence can come from one or more of the following sources:

• An official announcement or acknowledgment by the government of the country in question that it has developed and tested a nuclear weapon.

• Confirmation from a recognized international organization (e.g., International Atomic Energy Agency, Comprehensive Nuclear-Test-Ban Treaty Organization) or a major intelligence agency (e.g., CIA, MI6, FSB) that the country in question has developed and tested a nuclear weapon.

• Detection and verification of a nuclear test by a global monitoring network, such as the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), with widespread international consensus on the identity of the country responsible for the test.