Rubezh 2026 Turns CSTO into Russia's Southern Shield Against Afghan Threat

One and a half thousand servicemen and a new geography of risk

The most important figure from the recently concluded exercises "Rubezh-2026" on September 19 is not 300 units of equipment or even 115 drones, but four states out of six CSTO members. Russia, Kazakhstan, Kyrgyzstan, and Tajikistan practiced at the Koktal training ground in the Zhetysu region of Kazakhstan the repulsion of an invasion by illegal armed formations in mountainous and desert terrain. Armenia and Belarus did not participate in the active phase. For an alliance often accused of political decorativeness, this is not a trivial matter: the practical core of the organization is increasingly shifting from the European direction to the Central Asian border.

The official description of the CSTO does not name Afghanistan as the adversary in the scenario. However, reports on the maneuvers from 24NewsHD and Pakistan TV Digital directly link them to the risk of armed groups infiltrating from Afghan territory. This is an important caveat. Moscow avoids publicly turning "Rubezh" into an anti-Islamist operation against a specific regime while simultaneously preparing troops for the most likely type of crisis—not a classic invasion, but the infiltration of mobile groups through a poorly controlled border.

Why Tajikistan Became the Center of Collective Defense

Tajikistan has the only direct border with Afghanistan among CSTO members, stretching about 1357 kilometers. At the end of 2025, attacks that killed five Chinese citizens and two Tajik border guards made this border a political issue for Moscow rather than an abstract line on a map. On September 8, Russian Defense Minister Andrei Belousov named its fortification as one of the regional priorities. At the end of August, CSTO Secretary General Taalatbek Masadykov announced preparations for the first autumn supply of weapons and equipment for the Tajik border service.

In this context, "Rubezh" serves two functions. The military function is to test the ability of contingents to quickly deploy, integrate reconnaissance, fire strikes, and block infiltration routes. The political function is to demonstrate to Dushanbe that Russia offers not only bilateral promises but also a multilateral support mechanism. For Tajikistan, this is particularly significant: it seeks assistance but does not want to turn its own security into formal Russian military guardianship.

The scenario also reflects a change in the very concept of "collective security." It is not about a tank army crossing the border, but about small groups, drone reconnaissance, smuggling, drug trafficking, and propaganda. According to data cited by 24NewsHD referencing UN estimates, about 15,000 to 20,000 militants are active in Afghanistan, linked to approximately twenty groups; the Russian estimate reaches 23,000. These numbers should not be taken as an exact registry, but they explain why the CSTO is preparing not for a parade defense but for a system of constant monitoring and rapid local operations.

Drones as a Test of the Russian Military School

The presence of 115 UAVs among more than 300 units of equipment is the most telling detail of the exercises. After Ukraine, the Russian General Staff can no longer view drones as merely auxiliary reconnaissance tools. In the Central Asian scenario, they simultaneously provide group search, fire adjustment, gorge control, and operation result assessment. However, drones also create a reverse problem: the same infrastructure is needed to counter enemy drones, which can be used for surveillance, delivering explosives, and striking checkpoints.

This aligns with the decisions made at the 24th meeting of the CSTO Military Committee chaired by the Chief of the Russian General Staff Valery Gerasimov. In the official statement, the organization specifically recommended including unmanned systems, electronic warfare means, and air defense in national contingents, as well as transferring the experience of modern conflicts into joint training. The wording is bureaucratic, but the meaning is quite practical: Moscow is trying to standardize those elements of combat management that the war in Ukraine has forced to develop rapidly and often improvisationally.

However, here the limits of Russian leadership become apparent. Russia can offer doctrine, instructors, and some equipment, but it itself suffers from a shortage of modern communication means, electronic warfare, and cheap interceptors. If the CSTO copies the Russian model without a common industrial base and unified data exchange, the "collective" system will remain a set of national units connected only during exercises. On the training ground, this looks like an alliance. In a crisis, it may turn out to be merely a coalition of neighbors with different protocols and varying political will.

Southern Turn Instead of Block Unity

Belarus and Armenia's absence in the active phase is not coincidental, although their reasons differ. Minsk is traditionally oriented towards the West and Russian-Belarusian military integration. Yerevan, after the crisis surrounding Nagorno-Karabakh, has publicly distanced itself from the CSTO. Therefore, "Rubezh-2026" cannot be considered proof of the organization's full revival. It is rather an honest snapshot of its current structure: Russia uses the CSTO where the interests of Moscow, Dushanbe, Astana, and Bishkek genuinely intersect.

This is where the strategic value of the maneuvers lies for the Kremlin. Central Asia allows Russia to maintain its role as the main security provider even when its resources are consumed by the war in Ukraine. However, the role of mediator will have to be paid for with weapons, logistics, and a constant presence. If supplies to Tajikistan are delayed, and joint standards remain at the level of communiqués, trust in Moscow will diminish faster than victorious reports are published.

"Rubezh-2026" does not prove that the CSTO has become a full-fledged military alliance. It shows something else: the organization has developed a specific southern fear around which practical cooperation is still possible.

In the coming years, the CSTO will likely develop as a network of limited regional mechanisms rather than as a unified front. Provided that the threat from Afghan groups persists, Russia will strengthen the Tajik direction and continue to impose UAV, electronic warfare, and air defense standards on its allies. But if Moscow demands not only participation in exercises but also political loyalty on all issues, the southern shield will quickly turn into yet another symbolic facade of post-Soviet security.