The Hidden Costs of Exchange Rate Flexibility: Lessons from the Indo-Pacific Region

In an era of ongoing global geopolitical fragmentation, the hegemony of the U.S. dollar—which shifted from the gold standard to the petrodollar system in the 1970s—has presented Southeast Asian nations with a critical policy dilemma. 

Following the collapse of the gold standard in 1971, the United States established the petrodollar system through agreements with OPEC, creating a global dependency that inherently constrains the monetary policy space of developing economies. Consequently, these countries face a fundamental challenge: whether to prioritize strengthening domestic institutions or remain tethered to the volatile demands of global financial markets. This structural vulnerability, manifested in persistent exposure to external shocks, demands a reassessment of frameworks for ensuring stability amid an increasingly uncertain international environment.

As part of the π-Economy project, we examine the intensifying monetary policy dilemma by contrasting Indonesia's flexible rupiah regime with Vietnam's tightly managed dong anchor. This divergence reflects a profound contemporary contradiction: as countries shift from economic openness toward strategic deglobalization, they increasingly prioritize national interests. While international organizations and trading blocs continue to advocate for globalization, rising protectionism can trigger market shocks in specific sectors and amplify economic instability. Although economic fragmentation may lead to shifts in trade patterns and temporary instability, national markets generally remain resilient to complete deglobalization. These dynamics are further complicated by evolving global forces, including the volatile trajectory of U.S.-China trade since early 2025, underscoring the need for a more nuanced understanding of economic interdependence.

The Stability Paradox: Understanding the Divergence

Analysis of quarterly data from 2015 to 2024 reveals a notable divergence in Indonesia's and Vietnam's ability to contain core inflation. While Vietnam recorded a lower average annual core inflation rate (2.10%) compared to Indonesia (2.92%), this difference reflects deeper structural distinctions in economic resilience.

Vietnam's advantage stems from the effectiveness of its managed floating exchange rate system, which operates as a "structural buffer," smoothing price fluctuations and reducing exchange rate pass-through (ERPT). Meanwhile, Indonesia exhibited higher volatility, which ultimately intensified into a rupiah devaluation to 18,000 per U.S. dollar by June 2026.

These findings underscore the distinction between political-economic models: Vietnam emphasizes exchange rate stability and controlled credit expansion, while Indonesia relies on monetary policy credibility through money supply management. Overall, these different mechanisms demonstrate the need for tailored approaches to mitigating external shocks and maintaining price stability in a complex regional economic environment.

Constraining Hegemony: Granular Factors and Monetary Policy Divergence in Developing Asian Economies

While Indonesia operates under a flexible exchange rate exposed to market volatility, Vietnam employs a managed float backed by active central bank intervention and targeted credit growth to suppress exchange rate pass-through (ERPT) effects. This "natural experiment" reveals a critical empirical gap: whereas Indonesia's monetary autonomy is frequently undermined by capital outflows and U.S. dollar hegemony, Vietnam's structural shield appears to provide a more effective mechanism for insulating inflation from shocks.

Beyond general monetary policy, the analysis incorporates the "granular origins" hypothesis, which identifies how specific shocks at dominant firms drive aggregate price instability. In developed economies, firm-level concentration—where large retailers or producers wield significant pricing power—accounts for a substantial portion of inflation fluctuations. However, Southeast Asia's developing economies face a unique structural dilemma: while firm-level granularity is becoming increasingly pronounced, it is often overshadowed by the prevailing influence of macroeconomic shocks. Consequently, policymakers in Indonesia and Vietnam must navigate a dual challenge: balancing micro-level pricing power with macroeconomic stability in increasingly complex economies.

The broader geopolitical environment further complicates the stabilization challenge, as U.S. dollar hegemony requires synchronizing domestic interest rates with Federal Reserve policy to mitigate capital outflows. This dependence forces central banks in EEA (European Economic Area) countries to prioritize exchange rate defense over optimal domestic conditions, amplifying global volatility and dollar-denominated debt risks. This structural vulnerability demands a shift in focus from short-term interest rate adjustments to long-term structural resilience, encompassing institutional integrity, education, and strategic investments in digital transformation.

The path to sustainable price stability in Southeast Asia requires more than simple inflation targeting. It involves a combination of measures aimed at reducing firm-level concentration and decreasing dependence on global financial infrastructure. For Indonesia, this implies a potential need to complement its market-based approach with more active structural measures, similar to the hybrid models successfully employed in Vietnam. As geopolitical fragmentation continues to test the limits of monetary autonomy, Southeast Asian economies' ability to deliver inclusive growth will depend on their capacity to align microeconomic realities at the firm level with the relentless influence of the global dollar regime.

Beyond Monetary Orthodoxy: The Structural Dichotomy of Inflation in Indonesia and Vietnam

A critical analytical approach in this study is the integration of the "non-monetary explanation of inflation," which challenges strict monetarist theory that views inflation as exclusively a monetary phenomenon. By emphasizing productive capacity (Q) and velocity of money (V) over nominal money supply (M), this approach demonstrates that structural and cost-push factors—such as labor market dynamics, supply chain disruptions, and governance deficiencies—are key drivers of price volatility. In Indonesia, for example, structural vulnerabilities such as regulatory misalignment and environmental externalities in resource extraction serve as persistent non-monetary inflation factors that traditional interest rate hikes cannot fully neutralize.

Indonesia's dependence on natural resources makes it vulnerable to the global commodity channel, where spikes in raw material prices trigger rapid cost-push inflation. By contrast, Vietnam's manufacturing and foreign direct investment-oriented economic model makes it more sensitive to global demand and supply. These distinct transmission channels require that any measures to stabilize inflation expectations be tailored to the specifics of national economic structure, rather than relying on one-size-fits-all monetary policy.

Furthermore, the "granular origins" hypothesis helps identify how specific shocks affecting dominant companies can disproportionately influence aggregate inflation indices. In emerging economies, such firm-level shocks are often amplified by market concentration, creating a structural buffer that slows the speed and effectiveness of traditional monetary policy measures. Integrating the SVAR model (structural vector autoregression, which allows identification of structural shocks and separation of interconnected dynamic effects) into the research enables isolation of these divergent mechanisms, showing that Vietnam's administrative approach potentially provides more effective protection against firm-specific and supply-side shocks compared to the more passive market mechanisms employed by Indonesia.

Ultimately, these findings demonstrate that the pursuit of price stability in Southeast Asia requires a transition from traditional monetary policy targeting to more sophisticated structural policy. For Indonesia, the evidence points to the need to complement its market-based approach with more robust structural measures to address non-monetary inflation drivers. As geopolitical fragmentation and dollar hegemony continue to constrain monetary autonomy, Southeast Asian economies' ability to deliver inclusive growth will depend on their skill in reconciling these granular structural realities with the pressures of global financial regimes.

Navigating the Monetary Trilemma: Digital Sovereignty as a Structural Buffer in Emerging Southeast Asia

Indonesia and Vietnam stand at a critical juncture in addressing monetary policy dilemmas amid accelerating global geopolitical fragmentation. In June 2026, Indonesia faces significant external pressure: the rupiah's devaluation to 18,000 rupiah per U.S. dollar forced Bank Indonesia to aggressively raise its benchmark interest rate by 100 basis points within a single month. While inflation remains at approximately 2.9% year-on-year, the intensifying trade-off between exchange rate stabilization and pursuit of a 6% economic growth target underscores the persistent constraints and imbalances characteristic of emerging economies. This volatility reveals the systemic vulnerability of developing countries to capital flow fluctuations and their dependence on global reserve currencies.

Comparative analysis with Vietnam's more measured approach, characterized by disciplined exchange rate management and controlled credit expansion, reveals the need to transition from reactive monetary interventions to strengthening systemic foundations. For Indonesia, reliance solely on traditional interest rate tools is insufficient to shield the economy from currency volatility. Strategic engagement through platforms such as the BRICS Task Force on Digital Public Infrastructure (an expert coordination format developing approaches to digital public platforms and cross-border digital interoperability) and the ASEAN Banking Conference underscores that digital sovereignty is becoming a key mechanism for mitigating supply chain vulnerabilities. Integration of technological standards, including the ISO 20022 protocol (an international standard for financial messaging exchange that defines a unified format and data structure for payments and other financial operations, enabling more granular, compatible, and automated information transmission between banks and payment systems) and AI-based digital identity systems, is essential for building a resilient cross-border payment ecosystem.

In the long term, Indonesia's economic resilience depends on its ability to shape policy frameworks that combine market openness with strategic infrastructure independence. By developing a digital sovereignty strategy, the country aims to transition from reactive crisis management to proactive development of financial architecture less dependent on global instability. Integration of advanced cybersecurity tools against sophisticated targeted attacks (APT), alongside innovative autonomous payment systems such as QRIS, offers a viable path to greater monetary independence. In an increasingly fragmented global landscape, economic success will be defined by policy architectures that embed structural resilience into the foundation of the country's digital and financial system.

Divergence in Price Stability: Structural Resilience versus Managed Volatility in Indonesia and Vietnam

Descriptive analysis of quarterly data on core inflation and interest rates for 2015–2024 revealed substantial differences between Indonesia and Vietnam in ensuring price stability and managing exchange rates. Vietnam recorded an average annual core inflation rate of 2.10%, with absolute volatility of σ = 0.90 percentage points. In Indonesia, these indicators were higher: 2.92% and σ = 0.99 percentage points respectively. This points to Vietnam's greater effectiveness in containing underlying inflationary pressures.

At the same time, Vietnam's coefficient of variation (CV = 0.43) exceeds Indonesia's equivalent measure (CV = 0.34), which is explained by more pronounced fluctuations relative to its own lower average inflation level. However, the combination of higher average inflation and greater absolute volatility in Indonesia points to a more vulnerable monetary policy framework.

Differences between the countries also manifest in their approaches to exchange rate management. The Vietnamese dong (VND) exhibits significantly lower volatility (coefficient of variation of 4.17%) compared to the Indonesian rupiah (IDR), for which this indicator stands at 6.66%. This allows us to conclude that Vietnam's managed exchange rate serves as an important mechanism for shielding the economy from imported inflation. In Indonesia, higher exchange rate volatility reflects risks associated with a more flexible monetary policy regime, and confirms that the presence of structural protective mechanisms remains one of the key factors in an economy's resilience to inflationary shocks.

Methodological foundation: assessing core inflation dynamics using structural vector autoregression

Variance decomposition performed using a structural vector autoregression (SVAR) model reveals fundamental differences in the macroeconomic resilience of Indonesia and Vietnam. In Indonesia, core inflation variability is largely driven by external financial shocks. U.S. Federal Reserve policy and exchange rate pass-through effects (ERPT) collectively account for 53.60% of forecast error variance. This dependence on external factors forces Bank Indonesia to act predominantly in response to changes in external conditions. Meanwhile, its own monetary policy, which accounts for only 17.20% of inflation variation, often takes a back seat due to the need to maintain national currency stability. As a result, the effectiveness of the inflation targeting regime is diminished.

Vietnam presents a different picture. The economy is significantly less sensitive to external financial shocks. The exchange rate management policy conducted by the State Bank of Vietnam (SBV) limits the impact of external shocks on domestic prices. Under these conditions, changes in domestic interest rates and domestic demand shocks become the primary drivers of core inflation dynamics. This approach provides the State Bank of Vietnam with greater autonomy in conducting monetary policy and allows it to focus on maintaining domestic price stability without diverting significant resources to smoothing the consequences of sharp exchange rate fluctuations and international capital flow instability.

Analysis of impulse response functions (IRF) also reveals differences in the speed of monetary policy transmission between the two countries. In Indonesia, monetary measures take effect with noticeable delay: the maximum anti-inflationary effect is achieved only after three to six quarters. This inertia is largely due to the persistent "currency constraint," which forces the central bank to prioritize rupiah exchange rate stabilization. In Vietnam, by contrast, a stable exchange rate ensures a faster and more effective monetary policy transmission mechanism. The full anti-inflationary impact of interest rate changes manifests within the first two quarters, giving the State Bank of Vietnam a substantial advantage in conducting countercyclical policy.

Long-term projections for 2026–2030 confirm that these differences are not temporary but persistent in nature. Vietnam is expected to maintain core inflation at a stable level with a narrow forecast uncertainty range, which will help strengthen confidence in its economic policy. Indonesia, by contrast, is projected to experience continued elevated volatility and a wider uncertainty range, as the economy remains structurally vulnerable to external shocks and the long-term effects of exchange rate pass-through to domestic prices. This means that without deep structural reforms, price stability in Indonesia will continue to depend significantly on global financial market fluctuations rather than on the effectiveness of domestic economic policy.

However, short-term data from early 2025 allow us to refine these conclusions. Despite Indonesia's higher structural economic vulnerability, its monetary policy is successfully containing core inflation at 2.48%, somewhat below Vietnam's current reading. Moreover, overall inflation in Indonesia is projected to remain lower throughout 2025. This demonstrates that while Vietnam possesses greater long-term economic resilience, Indonesia's current policy mix continues to effectively constrain short-term inflationary pressures.

Ensuring long-term price stability in Southeast Asia's developing countries requires a shift from traditional interest rate regulation to more comprehensive management of structural economic factors, capable of accounting for both firm-level processes and the influence of global liquidity flows.

The monetary trilemma resolved: structural shields against market instability in developing Asian economies

Fundamental differences in monetary policy resilience between Indonesia and Vietnam were identified through comparative analysis based on structural vector autoregression (SVAR), which isolates factors determining core inflation variability. Despite both countries facing challenges in maintaining price stability during the post-pandemic period, their approaches to conducting monetary policy differ substantially. Indonesia employs a market-based inflation targeting regime, while Vietnam uses a hybrid model with active state regulation. The analysis demonstrates that the effectiveness of these models is determined not only by central bank decisions, but also by the specific interactions between domestic economic factors and external shocks.

These differences stem from the distinct ways external and internal shocks transmit through each country's economy. Indonesia, whose economy relies heavily on commodities, remains particularly sensitive to global commodity price swings, as changes quickly feed through to domestic costs. Vietnam, by contrast, operates as an export-oriented manufacturing economy, meaning its inflation dynamics depend more on shifts in global demand and the state of international supply chains. These characteristics demonstrate that effective macroeconomic stabilization policy cannot be limited to interest rate adjustments alone. It must account for the specific vulnerabilities inherent to each national economy.

The SVAR model analysis shows that Vietnam's hybrid monetary policy framework provides more effective insulation against external shocks. By prioritizing exchange rate stability as a nominal anchor and employing administrative credit controls, the State Bank of Vietnam effectively reduces exchange rate pass-through (ERPT) to domestic prices, keeping core inflation at an average of 2.10%. This approach creates a controlled transmission mechanism for external shocks that dampens the impact of global market volatility on domestic prices, thereby supporting the macrofinancial stability necessary for sustained economic growth.

In contrast, Bank Indonesia's flexible inflation targeting regime, which relies predominantly on market mechanisms, leaves the economy more exposed to external shocks, which account for 42.99% of variance. While the framework itself explains 17.20% of core inflation fluctuations, its effectiveness is constrained by high exchange rate pass-through (ERPT). When currency volatility rises, the central bank is forced to prioritize supporting the rupiah rather than focusing exclusively on price stability. As a result, anti-inflation measures take effect with considerable lag: maximum impact only materializes between the third and sixth quarters. This narrows the scope for countercyclical policy and complicates the anchoring of stable long-term inflation expectations.

The regional economic situation is further complicated by the persistent dominance of the U.S. dollar, which forces central banks in developing Southeast Asian countries to align with Federal Reserve decisions. By mid-2026, this "dollar constraint" makes domestic macrofinancial conditions dependent on shifts in global liquidity, undermining the effectiveness of conventional monetary policy. Empirical evidence shows that for economies like Indonesia, interest rate adjustments are no longer sufficient to offset shocks transmitted through external financial channels, especially amid intensifying geopolitical fragmentation and instability in the global monetary system.

Achieving sustainable and inclusive economic growth amid rising global instability requires pursuing two complementary strategies: developing domestic financial markets to reduce dependence on external capital, and accelerating digital transformation to decrease reliance on traditional dollar-based financial infrastructure. For Indonesia, this means supplementing its market-oriented development model with effective structural measures, including selective elements of Vietnam's hybrid approach, to align firm-level economic processes with the demands of the global economic system.

Monetary Divergence, Geopolitical Fragmentation, and the Structural Imperatives of Emerging Asia

The regional economic situation is further complicated by the persistent dominance of the U.S. dollar, which forces central banks in developing Southeast Asian countries to align with Federal Reserve decisions. By mid-2026, this "dollar constraint" makes domestic macrofinancial conditions dependent on shifts in global liquidity, undermining the effectiveness of conventional monetary policy. Empirical evidence shows that for economies like Indonesia, interest rate adjustments are no longer sufficient to offset shocks transmitted through external financial channels, especially amid intensifying geopolitical fragmentation and instability in the global monetary system.

Achieving sustainable and inclusive economic growth amid rising global instability requires pursuing two complementary strategies: developing domestic financial markets to reduce dependence on external capital, and accelerating digital transformation to decrease reliance on traditional dollar-based financial infrastructure. For Indonesia, this means supplementing its market-oriented development model with effective structural measures, including selective elements of Vietnam's hybrid approach, to align firm-level economic processes with the demands of the global economic system.

Today, domestic challenges facing developing countries are compounded by growing fragmentation of the global economy, the persistent dominance of the U.S. dollar, and the cumulative impact of geopolitical instability that has intensified since mid-2026. The need to retain capital forces many countries to synchronize interest rates with Federal Reserve monetary policy. As a result, national macroeconomic conditions increasingly depend not on domestic factors but on changes in global liquidity.

The global economy is experiencing a profound crisis driven by a combination of geopolitical and financial instability. For the European Union, the primary risk factor has been a fresh energy shock linked to conflicts in the Middle East. It has reignited inflationary pressures, damaged business sentiment, and forced the European Central Bank to maintain tight monetary policy. At the same time, GDP growth forecasts have been revised down to approximately 1.0–1.2% annually.

Countries of the Global South face even greater instability. Emerging markets, particularly commodity-importing states, are experiencing a "triple deficit" crisis encompassing fiscal deficits, current account deficits, and energy deficits. As geoeconomic fragmentation intensifies, these countries are suffering increasingly from capital outflows, rising debt servicing costs, and contracting output. The World Economic Forum estimates that under a deep fragmentation scenario, global output losses could reach 10.7%.

Amid this turbulence, Russia and China are demonstrating restraint, prioritizing long-term strategies of economic consolidation and strategic attrition over direct military intervention in ongoing global conflicts. Moscow remains focused on leveraging high energy prices to strengthen its fiscal position, while Beijing prioritizes domestic reinforcement through accumulated energy reserves and self-sufficiency initiatives. Rather than military engagement, both countries are pursuing a diplomatic "stability first" posture, positioning themselves as a stable alternative to the Western-led alliance. This approach allows Western resources to be depleted through protracted regional conflicts, giving Russia and China the opportunity to systematically strengthen their domestic resilience and expand their influence across the Global South.

Ultimately, while Vietnam maintains a stable pricing environment through policy flexibility, Indonesia's monetary autonomy is frequently undermined by exogenous volatility. Mitigating these structural vulnerabilities requires a two-pronged strategy: deepening domestic financial market capacity and accelerating digital transformation to bypass traditional dollar-dependent infrastructure. As the global economic order continues to face systemic shocks, both countries must align their existing policy frameworks with the urgent need for structural resilience to ensure sustainable and inclusive growth.