The Doomsday Clock has been advanced to 2.5 minutes to midnight—a setting closer to humanity’s extinction than any year since 1953. The Bulletin of the Atomic Scientists moved the minute hand forward by 30 seconds due to increasing existential threats from nuclear war, climate change, cyberwarfare, and potentially harmful innovations in biotechnology. The scientists stated the rise of terrorism and Donald Trump’s election as president of the United States increased the risk.

Trump’s presidency has ignited public concern over many social, political, and economic dangers, including global warming, xenophobia, and misogyny. These grievances are of vital importance, but the most catastrophic disaster that could occur during the next four years is much greater than any singular issue: Total nuclear annihilation.

A war that could lead to the extinction of humanity may sound extreme, but as two Nobel Prize-winning nuclear experts who advised both Reagan and Gorbachev during the Cold War, we have seen how very close humanity has been to nuclear war in the past—and we believe the global level of nuclear threat has once again been brought to its brink.

Yet as unlikely as it may seem, Donald Trump, the very man who has reinstalled this base fear, could also be the very person to lead the world toward nuclear disarmament.

The fact that a leader as inexperienced as Trump has access to nuclear launch codes that could destroy whole nations instantaneously has publicly reignited the issue of nuclear proliferation. However, the fundamental problem is not that Trump has access to the nuclear codes—it’s that they exist in the first place.

These grievances are of vital importance, but the most catastrophic disaster that could occur during the next four years is much greater than any singular issue: Total nuclear annihilation.

The lack of public concern about nuclear threat over the past two decades comes from a period of calm that followed the end of the Cold War, and the peculiar place that nuclear threat occupies in the human psyche. The problem is so horrible, and so beyond individual control, that it is suppressed. And what is suppressed cannot be countered.

Getting people to sit up and recognize that there is an unacceptable level of nuclear threat is an essential step to global nuclear disarmament; governments will not budge without public support. If anything, Trump’s presidency has re-alerted the world to the notion of nuclear annihilation and led to an awakening in social activism in younger generations.

We began our work against nuclear threat over four decades ago. As we are now in our seventies, we’re not going to solve this problem—you are. But before you can do your part, you first need to understand how we got here in the first place.

A brief history of the end of the world

The Doomsday Clock was first introduced in 1947, two years after the US detonated small nuclear weapons over Hiroshima and Nagasaki in Japan. By 1949, the Soviet Union had developed its own nuclear weapons, sending the two countries into a nuclear arms race. In a policy called “Mutually Assured Destruction,” or MAD, both sides threatened to annihilate the other if attacked. Children of our generation grew up in hiding under school desks as weekly air-raid sirens were tested.

The arms race continued throughout the 1970s and reached its peak under US president Ronald Reagan in the early 1980s. Both sides began to speak of a disarming first strike, which was a sudden attack to destroy the nuclear forces of the opponent. Each country therefore placed their weapons on “high alert,” so that they could fire them in less than 30 minutes and avoid being disarmed.

During this time, the public sensed an unacceptable level of danger. Young couples spoke of reluctance to bring a child into a world moving inexorably toward nuclear annihilation. Surveys of school children revealed widespread fear of a nuclear death.

IPPNW The International Physicians for the Prevention of Nuclear War recieving their Nobel Peace Prize in 1985. Dr. Muller is pictured second from the left and Dr. Pastore is on the far left.

By 1983, Reagan, aware of public opposition to the weapons, changed tactics by saying, “that a nuclear war cannot be won and must never be fought.” He and Soviet leader Mikhail Gorbachev even discussed the goal of complete abolition of nuclear weapons. The number of nuclear weapons in the world began to decrease from an absurd total of over 60,000 toward the current level of 15,000. Since a single nuclear weapon can destroy Manhattan or Moscow, the warheads that have been kept still far exceed the number required for deterrence. (In a little known story, much of the radioactive material in the decommissioned Russian warheads was sent to American nuclear-power plants. In 2009 it was estimated that 10% of the electricity consumed in the United States was produced with the use of salvaged bomb material.)

As the immediate threat of nuclear war decreased in the 1990s after the Cold War ended, we have had no reason to prioritize nuclear threat in the past 25 years. Other threats to human survival, such as global warming, have become the logical focus.

But the favorable progress made in the 1990s toward a world less at risk of nuclear annihilation has been reversed by three developments in the 21st century: first, the rise of terrorism as exemplified by 9/11; second, the proliferation of nuclear weapons from two to nine countries; and third, the re-emergence of a Cold War-style conflict between Russia and the US.

At the close of the 20th century, many rejoiced that the nuclear beast had been wrestled to the ground, but it has now arisen with renewed ferocity. Only the radical step of abolishing all nuclear weapons will slay it.

Where we stand now (but maybe not for much longer)

The US and Russia maintain an estimated 700 high-alert nuclear weapons each. This increases the risk of a hasty decision that could lead to nuclear war. The high-alert status is a remnant of the concern about a pre-emptive disarming first strike, but it is no longer needed for deterrence. (This is because adequate destructive force can now be delivered by nuclear weapons carried by submarines, which are not as vulnerable to an attack.) This therefore abolishes the need for the 30-minute high-alert status.

Though the US and Russia hold roughly 90% of the world’s 15,000 warheads, the weapons have now proliferated to a total of nine nations, including North Korea, India, and Pakistan. Terrorists have indicated a desire to obtain these weapons, and criminals have been apprehended selling the enriched uranium necessary to build a nuclear bomb.

We have had no reason to prioritize nuclear threat in the past 25 years. Other threats to human survival, such as global warming, have become the logical focus.

The nuclear threat was increasing prior to Trump’s victory. While the advancement of the clock from 3 to 2.5 minutes to midnight after Trump’s election has been widely noted, a greater advancement of the clock in 2015 from 5 to 3 minutes to midnight during Barack Obama’s presidency received little attention. The scientists at that time cited increased risk due to continued proliferation, a $1 trillion modernization program approved by the US government, and a halt of arms-control progress.

Also during the Obama administration, the United States refused to renounce the first use of nuclear weapons, and the Senate refused to ratify the Comprehensive Test Ban Treaty. The United States also opposed the UN resolution in support of a 2017 conference to abolish nuclear weapons, which was signed by 123 nations, including North Korea. All of this occurred as relations between the US and Russia deteriorated.

The US government’s most recent failures to take steps toward nuclear safety occurred during Obama’s leadership. Despite being a president dedicated to nuclear abolition and reduction of the nuclear threat, his efforts to reach those goals were hampered by an oppositional Congress, the nuclear-weapons portion of the military-industrial complex, a lack of public awareness of the problem, and hence, a lack of public support for the needed actions.

Trump’s stance on nuclear weapons

After his briefing on the nuclear codes, the new president himself said, “It’s very, very, very scary.”

It is, indeed, very scary.

While nuclear warfare was but a blip on the public’s radar during Obama’s years in office, the new Republican administration has immediately alerted the public to the presence of nuclear threat. Many are now terrified that Trump has his finger on a button that can launch over 700 nuclear weapons within 30 minutes, and a total of 1,300 other warheads that are ready to launch, according to the Federation of American Scientists.

Because of the high-alert status of the nuclear arsenal, there is no requirement for president Trump to consult anyone before deciding to launch a nuclear weapon. The Congress, which was granted the power to declare war by the Constitution, does not need to be consulted; the Supreme Court would also have no say. Once Trump decides to launch a missile, the order would travel through the military chain of command, which is composed of individuals who are committed to the security of the country—and trained to follow orders. Once launched, a missile cannot be recalled.

There is a distinction between the need to launch a nuclear weapon rapidly in response to a real sign of an incoming nuclear attack versus the deliberate decision to introduce nuclear weapons into a non-nuclear conflict. The latter is described as the “first use” of nuclear weapons, such as occurred in Hiroshima. Recently, Massachusetts senator Edward Markey and California representative Ted Lieu have proposed legislation to prohibit any president from introducing nuclear weapons into a conflict without a declaration of war from Congress. However, it is very unlikely that this proposal will ever reach the Republican-led Congress.

While there is great concern that president Trump’s finger is on the button (for either first use or retaliation), it is madness that humans, with great intelligence and industry, have created a system to so easily destroy the world—and then give control of the vast destructive force to any single person.

We still don’t entirely know what Trump thinks of nuclear weapons—but his words are surprisingly mostly positive. In 1987, he stated in an interview with a nuclear expert that he was working with governmental officials to reduce nuclear threat, citing the influence of his uncle John Trump, an MIT physicist. “Because I’ve become convinced that Trump’s involvement [in nuclear non-proliferation] is, well, serious,” Ron Rosenbaum wrote in 1987, “I have to abandon all the easy jokes and wisecracks I could have made if I thought it was some weird ego trip by an overambitious real estate promoter eager to thrust himself into the national arena.”

But what about in 2017? While running for office, Trump stated that “the single greatest problem the world has is nuclear”—but then in December 2016, then president-elect Trump sent an ambiguous tweet about the nuclear threat.

Many interpreted this as a call to expand nuclear weaponry, perhaps in response to Russian president Vladimir Putin’s statement earlier in the day that Russia needed to “strengthen the military potential of strategic nuclear forces.” A Trump spokesperson later said that “strengthen” referred to the need to work against proliferation to rogue nations. But was that truly his intention? After all, he also supposedly remarked, “Let it be an arms race. We will outmatch them at every pass and outlast them all,” to MSNBC co-host Mika Brzezinski when asked about the tweet. This is comment is similar to those made by president Reagan early in his presidency, before he changed his tune toward abolition.

If Trump is truly in favor of nuclear disarmament, he may be the best-positioned world leader in recent history to move this effort forward.

If Trump is truly in favor of nuclear disarmament, he may be the best-positioned world leader in recent history to move this effort forward. The fear he has incited has had the unintended byproduct of increasing public awareness of this topic for the first time in decades. Then there are his close connections with Russia: He places a high priority on improving relations with the other country most deeply embroiled in the problem, and the selection of Rex Tillerson as secretary of state adds the strength of an individual experienced in working with Russia. He has also met with former secretary of state Henry Kissinger, who has recommended “Russia should be perceived as an essential element of any new global equilibrium, not primarily as a threat to the United States.” Add to this the fact that the Democrats likewise do not wish for Trump to be anywhere near “the big red button,” so proposals he puts forward in Congress toward nuclear abolition should be met with some degree of bi-partisan support.

Oddly enough, nuclear non-proliferation might be about to have its moment.

How do we solve the world’s nuclear-weapon problems?

There are three actions Trump could take with Russia to decrease the nuclear threat:

First, as advocated by president Reagan, establish the goal “that nuclear weapons be banished from the face of the Earth.” A concrete step toward this goal would be for the US to reverse its opposition to the UN Nuclear Abolition Conference in March 2017 to negotiate a treaty to prohibit nuclear weapons.

Second, remove all weapons from high-alert status. There are many ways to decrease readiness to launch: The launch codes could me made less available, and for deeper safety, the warheads could be stored separately from the missiles that launch them.

Third, enhance efforts between the United States and Russia against nuclear terrorism. The former Soviet Union produced vast amounts of uranium and plutonium, which are the main ingredients for nuclear weapons. These fissile materials are not yet adequately protected from terrorists. Joint work has been done in the past and should be accelerated.

The fundamental problem is not that Trump has access to the nuclear codes—it’s that they exist in the first place.

Bold actions to reduce global nuclear threat require public support for what is a new mode of thinking. Our silent generation born in the mid-20th century huddled under desks as air-raid sirens screeched, and doubted we would survive. Later in the 1980s, humanity found its voice, and demanded a reversal of the arms race with a million-person march in New York City.

In 2017, public support for nuclear disarmament appears to be growing. Many, especially the young, have used electronic media and social networks to support the International Physicians for Prevention of Nuclear War (IPPNW), Global Zero, and the International Coalition to Abolish Nuclear Weapons (ICAN).

And now, it is your turn.

Movement toward safety is urgently needed. We have an iconoclastic president determined to change the status quo. Support for positive actions by president Trump on the nuclear issue is the best way for an individual to tip the balance from a march to extinction toward a path to safety.