Iran: The Eurasian Lock

January 22, 2026
Abbas al-Zein

Iran’s geography has turned it into a strategic hinge – one that anchors Russia’s southern depth and gives China an escape from US maritime containment.

In the corridors of US strategic decision-making, Iran is no longer treated as a discrete regional file. Dealing with Tehran has become inseparable from great-power competition itself. Coordination between Iran, Russia, and China has moved beyond situational alignment, coalescing into what western analysts increasingly describe as a form of “structural synergy” that undermines Washington’s ability to isolate its rivals.
This assessment overlaps with conclusions reached by the Carnegie Endowment in its report on America’s Future Threats, which identifies Iran as a “central node” in the Eurasian landmass – one that prevents Russia’s geographical isolation while securing China’s energy needs beyond the reach of US naval control.
Any serious destabilization of the Islamic Republic would not remain confined within its borders. It would translate into a dual strategic blockade targeting both China and Russia: reviving security chaos across Eurasia’s interior while striking at the financial and energy platforms that emerging powers increasingly rely on to loosen unipolar dominance.
Geography as strategic depth
For Moscow, Iran’s importance begins with geography. It offers Russia a vital geopolitical opening beyond its immediate borders. According to studies by the Valdai Club, Iran’s significance lies not in formal alliance politics but in its function as the sole land bridge connecting the Eurasian heartland to the Indian Ocean via the International North–South Transport Corridor (INSTC).
This route provides Russia with insulation from NATO’s maritime pressure in the Baltic and Mediterranean, effectively converting Iranian territory into strategic depth protecting Russia’s southern flank.
This geographic interdependence has produced a shared political interest that goes beyond tactical coordination. The stability of the Iranian state acts as a safeguard against the Caucasus and Central Asia drifting toward the kind of fragmentation that preceded the Ukraine war. Research by the Russian Council for International Affairs (RIAC) frames Iranian geography as a cornerstone of the “Greater Eurasia” concept, central to Moscow’s effort to dilute western hegemony across the continent.
For Beijing, Iran plays a comparable role within a different strategic equation. As US naval pressure tightens across the Pacific, China’s westward extension through Iran has become increasingly difficult to replace. Research by the Council on Foreign Relations (CFR) identifies Iran as one of the most critical geographic nodes in the Belt and Road Initiative (BRI), providing Beijing with a land-based corridor into West Asia that bypasses US-controlled maritime choke points – from the Taiwan Strait to the Mediterranean approaches.
Iran’s intermediate position between the Eurasian interior and open seas has therefore imposed a durable entanglement between Tehran, Moscow, and Beijing. In this configuration, political alignment is driven less by ideology than by physiogeographic necessity.
Any attempt to destabilize the Iranian plateau would likely trigger a cascading shock across Eurasia’s interior, escalating a regional confrontation into a systemic blockade aimed at arresting the rise of rival power centers.
Buffer state and security firewall
Beyond logistics, Iran functions as a stabilizing buffer within East Eurasia’s security architecture. One research report by RAND on “Extending Russia” speaks of adversary exhaustion strategies that emphasize the use of peripheral instability to drain rival powers. From this perspective, Iran represents a critical firewall.
Instability inside Iran would mechanically undermine security coordination across Russia’s southern periphery, particularly in the Caucasus and Central Asia. RIAC assessments warn that such a breakdown would open pathways for extremist networks, transcontinental smuggling, and militant spillover – threats Moscow has repeatedly classified as existential.
For China, the concern lies in contagion. Iran’s stability limits the transmission of unrest through Central Asia’s mountain corridors, where Tehran functions as an integral security partner within the Shanghai Cooperation Organization (SCO). This role provides Beijing with a degree of security insulation, allowing it to pursue global ambitions without being drawn into attritional border conflicts.
Energy and financial sovereignty
Economically, Iran’s role extends beyond conventional trade logic. Its partnerships with Russia and China increasingly form part of an alternative financial and energy architecture designed to blunt western leverage.
From Beijing’s perspective, Iranian oil has become a form of strategic insulation. Data indicates that China purchases roughly 1.3 million barrels per day (bpd) of Iranian crude – around 13.4 percent of its seaborne oil imports – with close to 80 percent of Iran’s exports flowing eastward. Increasing settlement through non-dollar mechanisms, including the digital yuan, has further reduced vulnerability to US pressure, particularly at choke points such as the Strait of Malacca.
Reports from the Electricity Hub confirm that China imported more than 57 million tons of Iranian – or suspected Iranian – oil in 2025, often routed via intermediaries such as Malaysia. The figures underscore the diminishing effectiveness of sanctions when confronted with geoeconomic necessity.
Russia’s calculus follows a different path to the same outcome. Cooperation with Iran has emerged as one of Moscow’s most important routes around SWIFT-based isolation. Government of the Russian Federation data shows bilateral trade rising by 35 percent following the Eurasian Economic Union free trade agreement implemented in May 2025.
A central shift has been monetary. In January 2025, the Central Bank of Iran announced full connectivity between Russia’s MIR and Iran’s Shetab payment systems, creating a protected financial corridor. According to Iranian officials, Iran and Russia aim to expand bilateral trade to $10 billion over the next decade, while Iran’s exports to Russia are expected to rise to about $1.4 billion by the end of the current Iranian calendar year (March 20, 2026).
Tehran has increasingly functioned as a re-export hub for Russian technologies and goods, frustrating efforts to economically isolate Moscow.
Washington’s strategy of separation
Against this backdrop, US strategy has evolved. Rather than relying solely on pressure or open confrontation, Washington has gravitated toward what western policy circles describe as a “strategy of separation.” This is an attempt to loosen the interdependence binding Tehran, Moscow, and Beijing by offering alternative pathways rather than confronting the bloc directly.
On the Chinese front, energy has emerged as the primary point of leverage. As the world’s largest oil importer, Beijing remains sensitive to supply stability and pricing. US moves in Latin America – particularly regarding Venezuela – are widely interpreted as efforts to reintegrate large oil reserves into global markets under western regulatory frameworks, potentially diluting Iran’s role in China’s energy security calculus.
In parallel, Washington has expanded its naval and coalition presence across key trade corridors stretching from the Indian Ocean to the western Pacific. This posture is framed not only as deterrence but as a persistent reminder that maritime supply security remains tied to US-led power balances.
On the Russian front, Ukraine occupies a central role. While sustained military and economic pressure aims to drain Moscow’s capacity, intermittent diplomatic signals suggest interest in compartmentalized understandings over European security. The underlying wager is that Russia’s core interests might be partially accommodated in Europe, reducing the long-term value of its partnership with Iran.
US engagement has also intensified across Central Asia and the Caucasus – regions that constitute strategic depth for Russia and critical corridors for China’s BRI. From Moscow and Beijing’s view, expanded security and investment ties in these areas represent an effort to geographically encircle Iran and weaken its role as Eurasia’s connective knot.
Why the bet fails
Despite the breadth of these efforts, the strategy of separation runs up against entrenched distrust in both Moscow and Beijing. For the two powers, the issue is not the scale of incentives on offer but the structure of the international system itself – and the accumulated experience of sanctions, coercion, and volatile western commitments.
From Russia’s vantage point, any trade-off between Iran and Ukraine constitutes a strategic trap. Iran anchors Russia’s southern access to the Indian Ocean; its collapse would expose the Caucasus–Central Asia arc to chronic instability. Gains in Eastern Europe would offer little compensation for a structurally weakened southern flank.
China’s reasoning is similarly grounded. Alternative energy suppliers remain embedded within supply chains that Washington can influence or disrupt. Iranian oil, by contrast, offers a higher degree of geographic and political autonomy. Its value lies less in price than in resilience.
The last barrier
At its core, the contest over Iran pits two logics against one another. One assumes geopolitical networks can be dismantled through incentives and selective realignment. The other recognizes that geography, accumulated experience, and the erosion of trust render such guarantees fragile in a world moving steadily toward multipolarity.
Iran’s collapse or prolonged internal destabilization would not merely reorder energy markets or regional alignments. It would reopen West Asia as a zone of near-exclusive US influence, completing a strategic arc across Western Eurasia. For more than a century, the region has served as a central theater of global power competition – from imperial rivalries to the Cold War and into the present transition toward multipolarity.
Therefore, Iran becomes more than a pivotal state. Much as Venezuela once represented the outer limit of resistance to US power in the Western Hemisphere, Iran now stands as the final geopolitical barrier to the consolidation of American hegemony across the heart of Eurasia.
Its cohesion serves not only its own national interest but also the broader objective shared by Moscow and Beijing: constraining unilateral dominance and preserving strategic autonomy in their immediate neighborhoods.