At a meeting of the G7 nations this week in Hiroshima, the first city destroyed by the bomb, President Joe Biden and other leaders have a chance to begin addressing the long-standing problem of states threatening to use nuclear weapons. Russia’s nuclear threats of the past year in support of its invasion of Ukraine have flashed for all to see a core purpose of nuclear arsenals: coercion and intimidation. At this historic gathering, Biden and his counterparts need to act on Japanese Prime Minister Fumio Kishida’s proposal that the G7 “demonstrate a firm commitment to absolutely reject the threat or use of nuclear weapons.”
To do so, the U.S. and its allies must acknowledge that any and all threats to use nuclear weapons, not just Russia’s, are unacceptable.
It is well known Hiroshima was destroyed without warning on August 6, 1945 by the U.S. Less familiar is that this devastation was followed that day by the first threat to use nuclear weapons. President Harry Truman threatened Japan “If they do not now accept our terms they may expect a rain of ruin from the air, the likes of which has never been seen on this earth.” Another threat came on August 9 when a second atomic bomb had destroyed Nagasaki; Truman announced “We shall continue to use it until we completely destroy Japan’s power to make war. Only a Japanese surrender will stop us.”
All G7 states (Canada, France, Germany, Italy, Japan, the U.K. and the U.S.) have condemned President Putin’s February, April and September 2022 threats of Russian nuclear weapons use. But like Russia those states themselves have chosen military strategies that depend on threats of nuclear weapon use.
A statement from the G7 nuclear nonproliferation directors group, issued April 17, predictably asserts that, unlike Russia, their nations’ security policies “are based on the understanding that nuclear weapons, for as long as they exist, should serve defensive purposes, deter aggression, and prevent war and coercion.” Just as predictably, Russian officials claim Putin’s comments are simply a deterrent against direct U.S. or NATO military intervention in Ukraine.
Regardless of intent, the underlying nuclear logic is the same, however. It was described by defense intellectual Daniel Ellsberg in a famous 1959 lecture “The Theory and Practice of Blackmail.” Ellsberg observed: “Nuclear weapons have one preeminent use in politics: to support threats. These threats recommend themselves, almost inescapably, as tools of policy not only to expansionist powers but to status quo nations.” He expounded: “Call it blackmail, call it deterrence, call both … coercion: the art of influencing the behavior of others by threats. The key here of course is that with nuclear weapons we are dealing with threats of force.”
Political scientist Richard Betts in his 1987 assessment of the cold war experience, Nuclear Blackmail and Nuclear Balance, observed, “the perception of whether a coercive threat represents legitimate deterrence or nasty blackmail is likely to depend on whether one is making the threat or facing it. And, in one respect the most significant thing about a threat is how it is seen by its target.” Other scholars note that from 1945 and throughout the cold war nuclear threats by U.S. leaders were risky and did not, generally speaking, work as intended.
Since the end of the cold war, the legal, moral and security contexts surrounding the threat to use nuclear weapons have been challenged by coalitions of nonweapon states, mostly from the Global South, as well as international organizations, especially the International Committee of the Red Cross, and nongovernmental organizations (NGOs) representing physicians, lawyers, scientists, peace activists and survivors of the atomic bombings and nuclear testing. A remarkable NGO-led campaign proceeded via the United Nations General Assembly to an International Court of Justice advisory opinion in 1996 that determined threatening to use nuclear weapons (as well as using them) is generally contrary to international law.
In 2017, backed by NGOs, a group of 122 nations at the U.N. agreed to the Treaty on the Prohibition of Nuclear Weapons (TPNW). Among its binding obligations is “never under any circumstances to … use or threaten to use nuclear weapons or other nuclear explosive devices.” There are almost 100 signatories to the treaty so far. No nuclear-armed state has signed.
In 2018, the U.N. Human Rights Committee concluded: “The threat or use of weapons of mass destruction, in particular nuclear weapons, which are indiscriminate in effect and are of a nature to cause destruction of human life on a catastrophic scale, is incompatible with respect for the right to life and may amount to a crime under international law.”
In June 2022, at their first meeting, TPNW states declared that “any use or threat of use of nuclear weapons is a violation of international law, including the Charter of the United Nations,” and condemned “unequivocally any and all nuclear threats, whether they be explicit or implicit and irrespective of the circumstances.”
The scale of destruction implied by threats to use nuclear weapons is beyond any moral measure.
In January 2023, Biden and Kishida made a joint statement “We state unequivocally that any use of a nuclear weapon by Russia in Ukraine would be an act of hostility against humanity and unjustifiable in any way.”
The caveat that such a judgment applies only to Russia in Ukraine is stunning.
If we are to avert catastrophe, the nuclear use policies of the United States and the other nuclear-armed states need to acknowledge that any and all threats to use nuclear weapons need to be treated alike. G7 leaders should look to a statement organized by the Physicists Coalition for Nuclear Threat Reduction, endorsed by more than 1,000 scientists, which states that “any threat to use nuclear weapons, at any time and under any circumstances, is extremely dangerous and totally unacceptable.” It goes on to “call on all people and governments everywhere to clearly condemn all nuclear threats, explicit or implicit, and any use of such weapons.”
As a first step, President Biden, along with the other G7 leaders, all of whose countries either have nuclear weapons or rely on U.S. nuclear weapons being used on their behalf, should declare that the U.S. and its allies will act as they demand others do, and will accept being judged by the same standards they apply to others. They must accept, without any self-serving caveat, that any use of a nuclear weapon, by any state, under any circumstances, would be “an act of hostility against humanity and unjustifiable in any way.”
If G7 leaders choose, the Hiroshima summit can mark their turning away from seeking to justify their own nuclear threats as acceptable tools of policy. It is time for a human-centered standard for judging nuclear threats, one that holds regardless of those making the threats, their targets or the political goal.
This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.