COVID-19, nuclear war, and global warming: lessons for our vulnerable world.

The COVID-19 pandemic teaches lessons we must embrace to overcome two additional existential threats: nuclear war and global warming. Health professionals need to send a message to those whose lives we have vowed to protect: all three threats result from forces of nature made dangerous by triumphs of human intelligence, and all three can be solved by human intelligence.1, 2, 3, 4, 5

Albert Einstein warned that “the unleashed power of the atom has changed everything save our modes of thinking and we thus drift toward unparalleled catastrophe”. The nuclear threat plus global warming led the Bulletin of the Atomic Scientists to advance the Doomsday Clock to 100 seconds before midnight—the closest ever—just before the pandemic.

Although it may seem overwhelming to contemplate additional threats during COVID-19, we must address all three since they are the greatest dangers ahead. Their origins and solutions are remarkably similar.

COVID-19 is the most visible. Had the outbreak happened before air travel, the mutant virus would have remained in China and spread slowly, if at all. Today, we face a permanent threat of future pandemics—genes will continue to mutate and planes will continue to fly.

Nuclear war is the least visible threat, as well hidden as the virus of a bat in a cave near Wuhan. It is, however, the most likely to have an immediate, devastating impact. In a city hit with a nuclear weapon, by intent or by accident, there would be no decisions about which patient to treat with the remaining ventilator.2, 3, 4

Global warming is the threat most certain to generate future harm, although human suffering will spread more slowly than with nuclear war or a pandemic.

The global response to COVID-19 is a source of hope. Scientists launched an inspiring counterattack on the coronavirus. Clinicians, often risking their own lives, rushed to bedsides.

The struggles against these threats teach valuable lessons. First, each threat must be recognised. Second, political leaders must respect truth and defer to expertise. Third, the threats are global and require global cooperation. Fourth, we all have to focus on our collective survival, and that includes care for the least privileged.

The world need not be the same after the pandemic. It can be better. A COVID-19-induced awakening can arrest our drift toward catastrophe. Health professionals, uniquely aware of the threats, have an obligation to enhance understanding of the requirements for survival in the 21st century.