IISS Warns: 2025 War May Have Lowered Nuclear Threshold

Synopsis

The International Institute for Strategic Studies has concluded that while the May 2025 India-Pakistan conflict stopped short of nuclear escalation, it may have lowered the threshold for future conventional military confrontation between the two nuclear-armed neighbours. Analysts also note that strengthened US-Pakistan ties following the conflict, including Islamabad's elevated role in mediating US-Iran talks, have fuelled Indian concerns about a perceived shift in American strategic alignment in South Asia.

What the 2025 Conflict Left Behind is beyond the Guns is the question you should be asking

Conflicts among states are sometimes constrained and calibrated in their scope, which can have repercussions much broader than those that are immediate and military. Analysts at the International Institute for Strategic Studies (IISS) believe the military standoff between India and Pakistan in May 2025, sparked by Operation Sindoor and the Pahalgam terrorist attack, has ushered in a series of strategic fallout consequences, some of which are just now being fully understood a year on.

In its analysis after the first year of the war, the IISS found that the conflict did not reach the nuclear level (which seemed too far from either side in the conflict itself) but had likely reduced the barriers to future conventional conflict. This evaluation assumes even more importance in a region that has two of the nine countries with nuclear arms: a country with a history of first-use policies and another with a history of strategic rivalry, albeit controlled.

The concept of nuclear threshold and its meaning

One of the key issues that is central to current strategic debate is the concept of a ‘nuclear threshold’, that is, the limit at which a non-nuclear war may be drawn into war of escalations using nuclear weapons. As regards India-Pakistan, both countries have been subject to the 'stability-instability paradox' that the presence of nuclear deterrence installs a false sense of security at the strategic level which could lead to an enhancement of the risks being taken at the lower level of conventional warfare.

The IISS's reasoning is that the fact that a limited conventional military clash between the two countries did not automatically escalate to nuclear war may have made such clashes more acceptable in the strategic thinking of both sides' governments. The more confident military planners on both sides are that a limited conventional blow may be taken and won't trigger a nuclear response the more likely they are to think about such a blow in future crises.

A Structural Shift in the US-Pakistan Relationship

One of the most important geopolitical repercussions of the 2025 war has been the U.S.-Pakistan bilateral relations. Cooperation in counterterrorism efforts between Islamabad and Washington has added to Pakistan's American strategic affirmation, as has its status as a key conduit in the U.S.-Iran diplomatic process, which has been more muted in the years leading up to the war.

Since May 2025, IISS analysts noted that the US-Pakistan relations have improved significantly. Islamabad's need is also becoming indispensable for the United States in a time when the focus of the United States has shifted to the conflict in West Asia, with the first round of direct talks with Iran in April 2026 being facilitated via Pakistan and regular diplomatic exchanges continuing from Islamabad.

In a strange way, "the 2025 conflict" has also strengthened Pakistan's diplomacy both regionally and with its important western partners, while also opening new fault lines in the existing complex structure of South Asian security.

"The 2025 conflict has paradoxically enhanced Pakistan's diplomatic standing, both regionally and with key Western partners, even as it has created new fault lines in the already complicated architecture of South Asian security." — International Institute for Strategic Studies (IISS) Annual Security Assessment

Indian Strategic Anxieties: Reading the US-Pakistan Signals

The upgrading of U.S.-Pakistan relations in the aftermath of the conflict is indeed a matter of great strategic unease in the eyes of New Delhi. India has long wanted to be America's favourite strategic partner in South Asia, cemented by a series of defence pacts, technology transfers and intelligence-sharing mechanisms brokered during the last two decades. That perception that Washington is moving toward Islamabad, albeit temporarily, is a challenge to that perception.

Indian worries are especially about the possibility of the US military and intelligence ties with Pakistan being further developed in ways that could compromise India's military advantage, an advantage it has always considered as a cornerstone of its deterrence capabilities against Pakistan. Technological transfers, diplomatic backing or a boost to the country's reputation that allows it to access more international defence markets is seen with some apprehension by Indian strategic players as it challenges the conventional edge.

Pakistan's high elevation: Diplomatic dividend of conflict

The way Pakistan has used the post-2025 war period to improve its image on the international forum requires an analysis. Islamabad's shift towards active mediation in the U.S.-Iran standoff — a move which placed it in a position to act as a responsible diplomatic player instead of a security-dependency client — is a sophisticated job in post-conflict diplomacy. The government of Pakistan, military and intelligence agencies seem to have played a tight game in leveraging Pakistan's geographical location and relations into diplomatic leverage.

The fact that both Washington and Tehran are willing to engage in sensitive diplomatic discussions via Pakistani middlemen will reflect the level of trust Islamabad has built up with both sides, which is valuable beyond the specific outcome of the US-Iran process. This volume is titled The Forward View: Managing an Increasingly Complex Deterrence Environment. This book is entitled The Forward View: Managing an Increasingly Complex Deterrence Environment.

A close reading of the IISS assessment, combined with the overall analytical commentary of institutions like the Carnegie Endowment for International Peace and the Stockholm International Peace Research Institute (SIPRI), suggests there are clear indications that the issue of strategic risk reduction requires constant dialogue between New Delhi and Islamabad. The talk, in today's political climate of both nations, is highly unlikely — a fact that gives the warnings of the strategic studies community so much weight.

A year into this conflict that the world watched with measured alarm, South Asia has a smaller conventional-competition versus nuclear-catastrophe divide than most South Asian governments would admit publicly — and a South Asian version of strategic prudence that has not always been the hallmark of bilateral relations.