The global arsenal of nuclear warheads exceeds 12,000, possessed by the world’s nuclear powers. These weapons have the capacity to cause direct casualties in the millions and, due to their potential impact on agriculture, could potentially result in the deaths of billions.
The deployment of nuclear weapons during the bombings of Hiroshima and Nagasaki in August 1945 caused fatalities ranging from 110,000 to 210,000. Since then, the world has faced numerous close calls with the potential use of nuclear weapons.
To curb the proliferation and reduce the number of nuclear weapons, international efforts have been made. This includes information on the number of states possessing nuclear weapons, the quantity of warheads in their possession, the nations opposing nuclear weapons, and the evolution of these dynamics over time.
Few countries possess nuclear weapons, but some have large arsenals
A limited number of nations possess nuclear weapons, with varying arsenal sizes. Currently, nine countries hold nuclear weapons: Russia, the United States, China, France, the United Kingdom, Pakistan, India, Israel, and North Korea.
Significant disparities exist among these nuclear powers in terms of the quantity of nuclear warheads they possess. The chart illustrates that, while most countries maintain dozens or a few hundred warheads, Russia and the United States possess thousands of them.
The specific number of nuclear weapons held by each country is treated as a closely guarded national secret, introducing significant uncertainty into the estimates provided here. Most nuclear-armed states offer little to no information regarding the sizes of their nuclear stockpiles. However, the level of secrecy varies among countries.
Between 2010 and 2018, the United States openly disclosed its total stockpile size, but this practice was halted by the Trump administration in 2019. In 2020, the Biden administration reinstated nuclear transparency briefly. However, it chose not to declassify any US stockpile data for 2021 or 2022. Similarly, in 2021, the United Kingdom announced its decision to no longer disclose public figures for its operational stockpile, deployed warhead, or deployed missile numbers. Furthermore, as of 2023, both the United States and Russia have opted not to exchange publicly available data about their deployed strategic warheads and launchers, as mandated by the New START Treaty.
Despite these challenges, publicly accessible information, meticulous analysis of historical records, and occasional leaks allow for the best possible estimates regarding the size and composition of national nuclear weapon stockpiles.
A lot of countries have given up obtaining nuclear weapons
The current count of countries possessing nuclear weapons is at its highest point in history. South Africa stands as the lone nation to completely dismantle its arsenal.
The chart indicates that numerous states have contemplated or actively pursued nuclear weapons, with the vast majority ultimately abandoning such endeavours. In the late 1970s, over a dozen countries explored or engaged in efforts to acquire nuclear weapons. In recent times, Syria has contemplated nuclear weapons, and Iran has been the sole country actively pursuing their development.
The number of nuclear weapons has declined substantially since the end of the Cold War
The number of nuclear weapons has experienced a significant decline since the conclusion of the Cold War. Following a continuous increase for nearly five decades since their inception in the 1940s, nuclear arsenals peaked at over 60,000 warheads in 1986.
However, a reversal of this trend is evident in the chart. Nuclear powers substantially reduced their arsenals in the subsequent decades, with the number of warheads dropping below 20,000 in the 2010s.
While the decline has decelerated in recent times, the total stockpile still surpasses 10,000 warheads, and some countries have even expanded their arsenals.
The destructiveness of nuclear arsenals has declined
The previous chart, which provided a straightforward count of the number of warheads, lacked consideration for the varying explosive power of these weapons and the constraints on simultaneous usage. The following chart endeavours to address this by factoring in the destructiveness and deployment of nuclear warheads, providing an estimate of the explosive power of weapons deliverable in a first strike.
Examining the data reveals that the United States rapidly developed significantly more potent warheads in the 1950s. While the Soviet Union increased the destructiveness of its weapons more gradually, it eventually reached comparable levels.
The destructive potential of first-strike warheads peaked at over 15,000 megatons (Mt) in the early 1980s, equivalent to more than a million Hiroshima bombs. At this zenith, these weapons could annihilate more than 40% of the total urban land worldwide.
Despite a steady decline in the destructiveness of first strikes over the decades for both the United States and the Soviet Union/Russia, it has remained above 2,500 Mt. This implies the potential to directly destroy almost 7% of the total urban land worldwide.
Nuclear weapons tests have almost stopped
Nuclear weapons states were once prolific in testing their warheads, with a peak of 178 tests in 1962, predominantly carried out by the United States and the Soviet Union. These tests had detrimental effects on the environment and people, particularly indigenous communities.
In subsequent years, the frequency of tests decreased, and in the last two decades, nuclear weapons testing has almost ceased. Notably, North Korea is the sole country that has conducted recent nuclear weapons tests.