How real is the risk of nuclear war between India and Pakistan?

In the latest India-Pakistan stand-off, determination were nary ultimatums, nary reddish buttons.

Yet the rhythm of subject retaliation, veiled signals and swift planetary mediation softly evoked the region's astir unsafe shadow. The situation didn't spiral towards atomic war, but it was a reminder of however rapidly tensions present tin summon that spectre.

Even scientists person modelled however easy things could unravel. A 2019 survey by a planetary squad of scientists opened with a nightmare scenario wherever a terrorist attack connected India's parliament successful 2025 triggers a atomic speech with Pakistan.

Six years later, a real-world stand-off - though contained by a US-brokered ceasefire connected Saturday - stoked fears of a full-blown conflict. It besides revived uneasy memories of however fragile stableness successful the portion tin be.

As the situation escalated, Pakistan sent "dual signals" - retaliating militarily portion announcing a National Command Authority (NCA) meeting, a calculated reminder of its atomic capability. The NCA oversees power and imaginable usage of the country's atomic arsenal. Whether this determination was symbolic, strategical oregon a genuine alert, we whitethorn ne'er know. It besides came conscionable arsenic US Secretary of State Marco Rubio reportedly stepped successful to defuse the spiral.

President Trump said the US didn't conscionable broker a ceasefire - it averted a "nuclear conflict". On Monday, successful an code to the nation, Indian Prime Minister Narendra Modi said: "[There] is no tolerance for atomic blackmail; India volition not beryllium intimidated by atomic threats.

"Any violent harmless haven operating nether this pretext volition look precise and decisive strikes," Modi added.

India and Pakistan each person astir 170 atomic weapons, according to the think-tank Stockholm International Peace Research Institute (Sipri). As of January 2024, Sipri estimated determination were 12,121 atomic warheads worldwide. Of these, astir 9,585 were held successful subject stockpiles, with 3,904 actively deployed - 60 much than the erstwhile year. The US and Russia unneurotic relationship for much than 8,000 atomic weapons.

The bulk of some India's and Pakistan's deployed arsenals lies successful their land-based rocket forces, though some are processing atomic triads susceptible of delivering warheads by land, aerial and sea, according to Christopher Clary, a information affairs adept astatine the University astatine Albany successful the US.

"India apt has a larger aerial limb (aircraft susceptible of delivering atomic weapons) than Pakistan. While we cognize the slightest of Pakistan's naval leg, it is tenable to measure that India's naval limb is much precocious and much susceptible than Pakistan's sea-based atomic force," helium told the BBC.

One reason, Mr Clary said, is that Pakistan has invested obscurity adjacent the "time oregon money" that India has successful gathering a nuclear-powered submarine, giving India a "clear qualitative" borderline successful naval atomic capability.

Since investigating atomic weapons successful 1998, Pakistan has ne'er formally declared an authoritative atomic doctrine.

India, by contrast, adopted a no-first-use argumentation pursuing its ain 1998 tests. But this stance has shown signs of softening. In 2003, India reserved the right to usage atomic weapons successful effect to chemic oregon biologic attacks - efficaciously allowing for archetypal usage nether definite conditions.

Further ambiguity emerged successful 2016, erstwhile then–defence curate Manohar Parrikar suggested India shouldn't consciousness "bound" by the policy, raising questions astir its semipermanent credibility. (Parrikar clarified that this was his ain opinion.)

The lack of a ceremonial doctrine doesn't mean Pakistan lacks 1 - authoritative statements, interviews and atomic developments offer wide clues to its operational posture, according to Sadia Tasleem of Carnegie Endowment for International Peace.

Pakistan's atomic threshold remains vague, but successful 2001, Khalid Kidwai - past caput of the Strategic Plans Division of the NCA - outlined 4 reddish lines: large territorial loss, demolition of cardinal subject assets, economical strangulation oregon governmental destabilisation.

In 2002, then-president Pervez Musharraf clarified that "nuclear weapons are aimed solely astatine India", and would lone beryllium utilized if "the precise beingness of Pakistan arsenic a state" was astatine stake.

In his memoir, erstwhile US Secretary of State Mike Pompeo wrote that helium was jolted awake astatine nighttime to talk with an unnamed "Indian counterpart" who feared Pakistan was preparing to usage atomic weapons during the 2019 stand-off with India.

Around the aforesaid time, Pakistani media quoted a elder official issuing a stark informing to India: "I anticipation you cognize what the [National Command Authority] means and what it constitutes. I said that we volition astonishment you. Wait for that surprise… You person chosen a way of warfare without knowing the consequences for the bid and information of the region."

During the 1999 Kargil War, Pakistan's then-foreign caput Shamshad Ahmed warned that the state would not "hesitate to usage immoderate weapon" to support its territory. Years later, US authoritative Bruce Riedel revealed that quality indicated Pakistan was preparing its atomic arsenal for possible deployment.

But determination is scepticism connected some sides implicit specified claims.

Former Indian precocious commissioner to Pakistan Ajay Bisaria wrote successful his memoir that Pompeo overstated some the hazard of atomic escalation and the US relation successful calming the struggle successful 2019. And during Kargil, Pakistan "knew the Indian Air Force wouldn't transverse into its territory" - truthful determination was nary existent trigger for adjacent an implicit atomic threat, importune Pakistani analysts.

"Strategic signalling reminds the satellite that immoderate struggle tin spiral - and with India and Pakistan, the stakes are higher owed to the atomic overhang. But that doesn't mean either broadside is actively threatening atomic use," Ejaz Haider, a Lahore-based defence analyst, told the BBC.

But atomic escalation tin hap by mishap too. "This could hap by quality error, hackers, terrorists, machine failures, atrocious information from satellites and unstable leaders," Prof Alan Robock of Rutgers University, pb writer of the landmark 2019 insubstantial by a planetary squad of scientists, told the BBC.

In March 2022, India accidentally fired a nuclear-capable cruise missile which travelled 124km (77 miles) into Pakistani territory earlier crashing, reportedly damaging civilian property. Pakistan said India failed to usage the subject hotline oregon contented a nationalist connection for 2 days. Had this occurred during heightened tensions, the incidental could person spiralled into superior conflict, experts say. (Months later, India's authorities sacked 3 aerial unit officers for the "accidental firing of a missile".)

Yet, the information of atomic warfare remains "relatively small" betwixt India and Pakistan, according to Mr Clary.

"So agelong arsenic determination is not large crushed combat on the border, the dangers of atomic usage stay comparatively tiny and manageable," helium said.

"In crushed combat, the 'use it oregon suffer it' occupation is propelled by the anticipation that your crushed positions volition beryllium overrun by the enemy." ('Use it oregon suffer it' refers to the unit a nuclear-armed state whitethorn consciousness to motorboat its weapons earlier they are destroyed successful a archetypal onslaught by an adversary.)

Sumit Ganguly, a elder chap astatine Stanford University's Hoover Institution, believes that "neither India nor Pakistan wants to beryllium labelled arsenic the archetypal violator of the post-Hiroshima atomic taboo".

"Furthermore, immoderate broadside that resorts to the usage of atomic weapons would look important retaliation and endure unacceptable casualties," Mr Ganguly told the BBC.

At the aforesaid time, some India and Pakistan look to beryllium beefing up their atomic arsenal.

With caller transportation systems successful development, 4 plutonium reactors and expanding uranium enrichment, Pakistan's atomic arsenal could scope astir 200 warheads by the precocious 2020s, according to The Nuclear Notebook, researched by the Federation of American Scientists' Nuclear Information Project.

And arsenic of aboriginal 2023, India was estimated to person astir 680kg of weapons-grade plutonium - capable for astir 130-210 atomic warheads, according to the International Panel connected Fissile Materials.

Despite repeated crises and adjacent calls, some sides person truthful acold managed to debar a catastrophic descent into atomic conflict. "The deterrent is inactive holding. All Pakistanis did was to respond to accepted strikes with counter-conventional strikes of their own," writes Umer Farooq, an Islamabad-based analyst.

Yet, the beingness of atomic weapons injects a changeless undercurrent of hazard - 1 that tin ne'er beryllium wholly ruled out, nary substance however experienced the enactment oregon however restrained the intentions.

"When atomic weapons tin beryllium involved, determination is ever an unacceptable level of danger,"John Erath, elder argumentation manager astatine the non-profit Center for Arms Control and Non-Proliferation, told the BBC.

"The Indian and Pakistani governments person navigated these situations successful the past, truthful the hazard is small. But with atomic weapons, adjacent a tiny hazard is excessively large."