On 1 February 2015, Iraqi Foreign Minister Ibrahim al-Jaafari declared that the War on ISIL was effectively "World War III", due to ISIL's declaration of a Worldwide Caliphate, its aims to conquer the world, and its success in spreading the conflict to multiple countries outside of the Levant region.On 1 February 2015, Iraqi Foreign Minister Ibrahim al-Jaafari declared that the War on ISIL was effectively "World War III", due to ISIL's declaration of a Worldwide Caliphate, its aims to conquer the world, and its success in spreading the conflict to multiple countries outside of the Levant region. In response to the November 2015 Paris attacks, King of Jordan Abdullah II said "We are facing a Third World War [within Islam]."
In his State of the Union Address on 12 January 2016, U.S. President Barack Obama warned that news reports granting ISIL the supposed ability to foment WWIII might be excessive and irresponsible, stating that, "as we focus on destroying ISIL, over-the-top claims that this is World War II
In his State of the Union Address on 12 January 2016, U.S. President Barack Obama warned that news reports granting ISIL the supposed ability to foment WWIII might be excessive and irresponsible, stating that, "as we focus on destroying ISIL, over-the-top claims that this is World War III just play into their hands. Masses of fighters on the back of pickup trucks and twisted souls plotting in apartments or garages pose an enormous danger to civilians and must be stopped. But they do not threaten our national existence."
In multiple recorded interviews under somewhat casual circumstances, comparing the conflagrations of World War I and II to the ongoing lower intensity wars of the 21st century, Pope Francis has said, "The world is at war, because it has lost peace," and "perhaps one can speak of a third war, one fought piecemeal."
In 1949, after the unleashing of nuclear weaponry at the end of WWII, physicist Albert Einstein suggested that any outcome of a possible WWIII would be so dire as to revert mankind back to the Stone Age. When asked by journalist Alfred Werner what types of weapons Einstein believed World War III might be fought with, Einstein warned, "I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones".
A 1998 New England Journal of Medicine overview found that "Although many people believe that the threat of a nuclear attack largely disappeared with the end of the Cold War, there is considerable evidence to the contrary." The United States – Russia mutual detargeting agreement in 1994 was largely symbolic, and did not change the amount of time required to launch an attack. The most likely "accidental-attack" scenario was believed to be a retaliatory launch due to a false warning. Historically, World War I happened through an escalating crisis; World War II happened through deliberate action. Both sides often assume their side will win a "short" fight; according to a 2014 poll, 3/4 of the public in China believes their military would win in a war with the U.S. Hypothesized flashpoints in the 2010s included Russian intervention in Ukraine, and Chinese expansion into adjacent islands and seas. Other hypothesized risks are that a war involving Iran, Israel, Pakistan, India, North Korea, or Taiwan, could escalate via alliances or intervention into a war between "great powers" such as the U.S., Russia, or China; or that a "rogue commander" under any nuclear power might launch an unauthorized strike that escalates into full war.
Some scenarios involve risks due to upcoming changes from the known "status quo". In the 1980s the Strategic Defense Initiative made an effort at nullifying the USSR's nuclear arsenal; some analysts believe the initiative was "destabilizing". In his book Destined for War, Graham Allison views the global rivalry between the established power, the US, and the rising power, China, as an example of the Thucydides Trap. Allison states that historically, "12 of 16 past cases where a rising power has confronted a ruling power" have led to fighting. In January 2020 the Union of Concerned Scientists advanced its Doomsday Clock, citing (among other factors) a predicted destabilizing effect from upcoming hypersonic weapons.
Emerging technologies, such as artificial intelligence, could hypothetically generate risk in the decades ahead. A 2018 RAND Corporation report has argued that AI and associated information technology "will have a large effect on nuclear-security issues in the next quarter century". A hypothetical future AI could provide a destabilizing ability to track "second-launch" launchers. Incorporating AI into decision support systems used to decide whether to launch, could also generate new risks, including the risk of an adversarial exploitation of such an AI's algorithms by a third party to trigger a launch recommendation. A perception that some sort of emerging technology would lead to "world domination" might also be destabilizing, for example by leading to fear of a pre-emptive strike.