“The prospect of a nuclear conflict that was once unthinkable is now back in the realm of possibility,” UN Secretary-General Antonio Guterres said on March 14. Nearly 70 percent of Americans surveyed by the American Psychological Society said they were “worried that the invasion of Ukraine would lead to a nuclear war and that they are in the early stages of World War III.” Researchers estimate that there are about 12,700 nuclear weapons distributed among nine countries, with the United States and Russia holding the majority. Zoom Icon Arrows pointing outwards Investigators and government officials say a nuclear attack is highly unlikely. “We are evaluating President Putin’s directive and, at the moment, we see no reason to change our own alarm levels,” said White House spokeswoman Jen Psaki on February 28. “As long as these weapons exist, there will always be the potential for real use,” said Alejandra Munoz, a project officer at the Dutch peacekeeping organization PAX. Researchers, academics and advocacy groups on risk reduction and nuclear disarmament have written reports detailing what a hypothetical attack might look like and the long-term impact it could have on the planet and society. See what a nuclear attack might look like and how the United States might react.