Counting weapons, building peace: how sharing information prevents escalation

At the height of the Cold War, one of the closest brushes with nuclear war didn’t come from aggression: it came from misreading a military exercise.

In 1983, a large-scale NATO exercise was misinterpreted as potential cover for a pre-emptive nuclear strike. Soviet alert levels were raised and military units mobilized before the situation was eventually defused through luck and back-channel diplomacy. No one had deliberately sought confrontation, but the danger came from the gap in understanding.

But luck is not a security strategy. The question is whether something more reliable can be built in its place and sustained over the years.

The gap between what countries know and what they assume is one of the oldest and most persistent sources of insecurity in international affairs. Closing it, even partially, is the idea behind confidence- and security-building measures, or CSBMsCSBMs
Confidence- and security-building measures. These are structured, verifiable arrangements through which States share information about their military activities among other measures, reducing the risk that misreading becomes miscalculation, and miscalculation becomes something worse.

Confidence- and security-building measures are the structured response to this problem. Through mandatory exchanges of military information, military contacts and co-operation, advance notification of exercises and troop movements, and mutual verification rights, CSBMs give countries verified insight into each other's military activities to avoid miscalculations or misunderstandings. 

These are not goodwill gestures. They are agreed commitments with compliance mechanisms attached to them. The result is not merely better information, but a clear reduction in the very conditions that allow miscalculation and escalation to take hold.

Building the architecture

The OSCE's work on arms control and confidence-building can be traced to the 1975 Helsinki Final Act. Participating States formally acknowledged what remains true today: that the risk of conflict is compounded when states lack clear and timely information about each other's military activities. Over the decades that followed, participating States developed a set of tools to put the principle into practice. 

The OSCE's primary instrument to do this is the Vienna Document, negotiated and strengthened through successive iterations since 1990. The current version, the Vienna Document 2011, binds all 57 OSCE participating States to a set of concrete, verifiable commitments. Under the Vienna Document, States must share detailed information about their military forces annually, defence planning and budgets, notify each other in advance of significant exercises and troop movements, invite observers to certain military activities and accept on-site inspections to verify that what they have declared matches what they actually hold. In addition, the Vienna Document 2011 enables States to raise security concerns to consult and co-operate in response to unusual, unscheduled and significant military activities, or hazardous military incidents. 

Underpinning all of this is the dedicated OSCE Communications Network, which provides a secure state-to-state channel through which governments can share and exchange information, clarify intentions, and dispel security concerns before ambiguity creates the conditions for escalation.

The Vienna Document is part of a wider system of mutually reinforcing arms control and confidence building measures that have long served as pillars for European security. The Treaty on Conventional Armed Forces in Europe, signed in 1990, established binding limits on specific categories of conventional military equipment across Europe, while the 1992 Open Skies Treaty enabled unarmed observation flights, giving any member state the right to fly over another and verify what was happening on the ground. At a time when full-scale war has returned to the region, the Vienna Document remains a valuable instrument in preventing further escalation.

Arms control agreements can seem abstract, negotiated in conference rooms far removed from the places they are meant to stabilise. The OSCE's experience in South-Eastern Europe shows how they can make a real difference on the ground.

South-Eastern Europe: a proof of concept

In 1996, soon after the conflict in Bosnia and Herzegovina ended, soldiers who had recently been on opposite sides began inspecting each other’s military facilities. This was not an easy process. The distrust was real, but it created a remarkable precedent. Former adversaries submitted to mutual scrutiny, making verification possible where trust was absent.

The framework for this was Article IV of the Dayton Peace Accords, signed in June 1996. Its mandate was clear: reduce conventional weapons to the lowest levels consistent with each party's security needs. Bosnia and Herzegovina, Croatia and what was then the Federal Republic of Yugoslavia agreed to binding ceilings on battle tanks, artillery, combat aircraft, attack helicopters and armoured vehicles. Weapons above those ceilings had to be destroyed.

What followed was painstaking, but successful. By November 1997, the parties had eliminated over 6,500 heavy weapons to reach their agreed limits. Reductions continued on a voluntary basis, below the agreed thresholds, long after the mandatory phase was complete. By 2026, more than 10,000 weapons had been destroyed in total. Over 830 inspections had been conducted, with nearly 1,300 arms control specialists and over 280 observers from 30 OSCE participating States taking part.

The OSCE's role was significant, particularly in the early years. The Office of a dedicated Personal Representative of the Chairpersonship in Vienna co-ordinated the inspection regime, while the OSCE Mission on the ground acted as mediator when political tensions threatened to stall the process. The Organization's role was always designed to diminish as the parties built their own capacity.

This transition was completed in 2014. Bosnia and Herzegovina, Croatia, Montenegro and Serbia assumed full responsibility for the implementation and adherence to Article IV, with the OSCE’s Conflict Prevention Centre moving into a purely supporting role. 

The work ahead

Thirty years ago, the idea that former adversaries in South-Eastern Europe would spend the following decades accounting for their weapons, submitting to mutual inspections and ultimately taking full ownership of the process would have seemed unlikely. Yet, it happened because a framework was put in place and the parties made a deliberate decision to use it.

The security environment in 2026 is considerably more challenging. The broader arms control architecture is under pressure. But the logic that underpins confidence- and security-building measures has not changed. States that share information, notify each other of their intentions and submit to verification are less likely to misread each other and less likely, as a result, to miscalculate and lead to more conflict.

That logic is why all 57 OSCE participating States are gathering at the Annual Security Review Conference (ASRC) in Vienna on 17 and 18 June the Organization's primary forum for dialogue on regional security challenges. 

Convened on the basis of a consensus decision by all 57 OSCE participating States, the ASRC provides a unique platform for inclusive discussions on the security situation across the region, underscoring their continued commitments to maintaining dialogue on security issues affecting the OSCE region. 

At the ASRC, senior officials will assess the security situation across the OSCE area, the kind of structured, face-to-face exchange that the logic of confidence-building depends on.

Verified transparency, grounded in goodwill and sustained over time, can transform relationships between former adversaries. It does not require trust to begin. It requires a space for dialogue, a framework, but most of all – the willingness to use it.