By Cate Warden*
We only hear about the relationship between nuclear-armed states India and Pakistan in abrupt times of crisis, such as when India accidentally fired a missile into Pakistan in March of 2022. The escalation dominates headlines for a few days, and then no one outside of the region itself hears about India and Pakistan’s unsteady relations for months to follow. However, despite the intermittent media coverage and lack of western public attention, the possibility of a nuclear war between India and Pakistan poses a genuine and ongoing threat to humanity and the environment.
While all tense relationships between nuclear powers are concerning, the relationship between India and Pakistan stands out since the two countries have already engaged in multiple conventional armed conflicts following Partition in 1947.
Frank O’Donnell, who is the current Deputy Director of the Stimson Center’s South Asia Program, said, “the nuclear competition between India and Pakistan overlays a territorial dispute over Kashmir, which has remained unresolved since 1947. The dispute is far from dormant, and efforts to change conditions on the ground have led to multiple wars and nuclear crises. Both states currently place little stock in the belief that their underlying dispute can be resolved through political dialogue, and instead pursue nuclear and conventional military options.” Operation Brasstacks, which was the largest historical mobilization of Indian forces along the Pakistani border, is a modern example of such tension, which brought the two countries very close to a conventional war.
The decades of conflict between the two countries and frequent escalation make an India-Pakistan nuclear war an unsettling possibility. India’s capabilities in conventional warfare far outweigh Pakistan’s; India’s “Cold Start” military doctrine allows the Indian military to theoretically mobilize large numbers very quickly, meaning that India could potentially swiftly defeat Pakistan in a conventional war. As a result, Pakistan relies on an extreme nuclear doctrine to counteract this perceived imbalance. Russia’s lack of military success in Ukraine, despite an even greater conventional advantage than India’s, has not changed the equation for Islamabad. Additionally, both India and Pakistan have both increased their nuclear arsenals in recent years.
Hans Kristensen, the current director of the Nuclear Information Project at the Federation of American Scientists, said, “when it comes down to nuclear weapons states that could end up in a nuclear clash against each other, India and Pakistan has for years been considered the most likely.”
Even a small nuclear encounter between India and Pakistan could have devastating environmental consequences, according to a 2019 study titled “How an India-Pakistan nuclear war could start—and have global consequences.” Rich Turco, a contributor to the study, said, “after an all-out nuclear war or even a relatively small superpower nuclear exchange, the climate could change dramatically.”
The hypothetical war outlined in the study would take place in the year 2025, by which it is predicted that India and Pakistan could each have about 250 nuclear weapons. The study predicts that by the end of the conflict, Pakistan will use all of its nuclear weapons. India, however, would use only about 150 of its weapons. The scenario posed is admittedly unlikely and highly dependent on the specific circumstances of the conflict; it should not be read as predictive but rather cautionary, given the severity of consequences from any nuclear exchange.
The long-term environmental impacts of a nuclear war between India and Pakistan would be caused by the smoke released into the atmosphere, and the amount of smoke would depend on the size of India and Pakistan’s strategic weapons. The study assumes that both countries use weapons roughly the size of the Hiroshima bomb, and predicts that a nuclear encounter between the two countries would inject more than 17 million tons of black carbon into the atmosphere. This carbon would then be heated by the sun and lifted to the stratosphere, where it would block sunlight from the Earth and create a worldwide nuclear winter. This catastrophe would halt agriculture, alter ocean temperature, and dangerously lower the global average temperature. Additionally, the study states that the smoke from a nuclear war would remain in the stratosphere for several years, meaning that the environmental impacts of a conflict between India and Pakistan would be long term. This is the most optimistic scenario outlined in the study—within the next few years, it is entirely possible that India and Pakistan will have developed much larger weapons with even more severe environmental consequences.
As the climate crisis worsens, the effects of a nuclear war could be even more dire. Turco said, “global warming is putting the human population in a precarious position. Climate-related issues are stressing the human community and nuclear winter, if it occurred under those conditions, would produce even more severe consequences because it adds an additional major problem to society. ” Turco went on to say that “as the environment changes, India and Pakistan are right in the front line of countries that are going to be affected, and a nuclear war would only exacerbate everything.” As climate change continues to stress resources and populations, it carries risks of triggering additional conflicts, which, in the case of South Asia, could increase the risk of nuclear weapons use.
It is absolutely crucial that the world sees India and Pakistan’s relationship for what it is: a present and existential environmental threat. Despite the clear connections between environmental concerns and nuclear risk reduction, it is rare to see the question of a nuclear war in South Asia included in environmental activism. The climate justice movement cannot ignore the potential environmental impacts of nuclear war between India and Pakistan, and the nuclear risk reduction movement cannot ignore the ways that climate change exacerbates the risk of nuclear war; both movements need each other.
*Editor’s note: Writing for the Center’s new Next Up in Arms Control series, Cate Warden is a high school senior from San Francisco. She first connected to the Center in 2021 while writing an opinion piece about the need for a new youth disarmament movement for her school newspaper.