In the first half of 2026, the US dollar index experienced a three-phase, volatile upward trajectory, driven by the interplay of geopolitical conflict, a shift in Federal Reserve policy, and improving US terms of trade. This dollar strengthening fundamentally reflects the end of the old global macroeconomic paradigm characterized by low interest rates and low volatility, and the emergence of a new regime marked by high inflation and high uncertainty. This analysis reviews the dollar's performance since 2026, deconstructs its multiple drivers, interprets new Fed policies, compares the divergent performance of various safe-haven assets, and assesses the outlook for the second half through risk scenario analysis, aiming to provide fundamental insights for foreign exchange and global asset allocation.
Review of US Dollar Index Performance in H1 2026
In the first half of 2026, the US dollar index rose by approximately 3.2%, reflecting a period of relative dollar strength. The market's core trading narrative shifted continuously throughout this period. The dollar's trajectory can be divided into three distinct phases: pressure from policy uncertainty, a rise in geopolitical risk premiums, and a repricing of monetary policy expectations.
Phase One (January): US Domestic and Foreign Policy Uncertainty Weighs on the Dollar
The year began with the global FX market still under the lagged influence of the previous administration's tariff policies, with trade uncertainty continuing to disrupt cross-border capital flows. In mid-January, public US geopolitical statements regarding Greenland further amplified market concerns about the instability of US foreign policy and rising unilateral policy risks. During this phase, the core market narrative was the weakening of US economic and policy advantages and a loosening of the 'American exceptionalism' story. Global risk capital, seeking safety, temporarily reduced exposure to dollar-denominated assets, leading to modest capital outflows from the US market and directly dragging the dollar index lower. By late January, it touched a first-half low of 95.77, a cumulative decline of 2.5% from the year's opening price. This decline was not supported by a weakening fundamental backdrop but was primarily driven by external policy risk expectations, representing a short-term sentiment-driven correction that also created valuation space for a subsequent rebound.
Phase Two (February-March): Escalation of Middle East Conflict Boosts Dollar via Safe-Haven and Energy Benefits
The full-scale escalation of US-Iran conflict in late February became the pivotal turning point for the dollar in the first half. Disruptions to shipping through the Strait of Hormuz posed a direct risk of a break in the global crude oil supply chain, rapidly fueling global stagflation fears and fundamentally repricing major asset classes. Data shows that in the ten trading days following the outbreak of conflict, the dollar index defied earlier trends, rising 2.82% to successfully breach the key 100 level, reaching a phase high of 100.51 by late March. This dollar strength had dual support: firstly, its traditional role as a global safe-haven currency came to the fore, attracting capital in times of crisis; secondly, as a net energy exporter, soaring oil prices directly improved US terms of trade, creating a fundamental premium independent of safe-haven demand. This dual resonance propelled the dollar index away from its previous range.
Phase Three (April-June): Fed Policy Pivot Drives Second Dollar Surge on Hawkish Expectations
Entering the second quarter, the Middle East conflict entered a stalemate, market pricing for geopolitical risk became more complete, and expectations of a ceasefire agreement caused repeated market volatility. The dollar index moved away from its highs into a range-bound pattern, largely confined between 97.60 and 99.50 during April-May, lacking clear directional momentum. The June Federal Reserve meeting became the quarter's most significant inflection point. On June 17th, new Chair Warsh held his first major post-appointment monetary policy briefing, striking a far more hawkish tone than market consensus. The latest dot plot showed most FOMC members supported at least one rate hike in 2026, completely overturning the market's previous consensus for a second-half rate cut. The rapid repricing of monetary policy expectations drove US Treasury yields higher across the curve. Widening interest rate differentials spurred significant capital flows back to the US, leading to a rapid rally in the dollar index, which touched a phase high of 101.37 on June 24th, a near seven-month peak. Monetary policy expectations officially replaced geopolitics as the core variable driving the dollar.
Deconstructing the Drivers: A Triple Resonance of Geopolitics, Trade, and Policy
The two major dollar rallies in H1 2026 were not driven by a single variable but resulted from the simultaneous resonance of three core factors: geopolitical restructuring, global energy price shocks, and a shift in the Federal Reserve's monetary policy paradigm. These factors supported dollar strength from three dimensions—market sentiment, macroeconomic fundamentals, and interest rate pricing—forming a robust upward logic loop.
Geopolitical Conflict Reshuffles Safe-Haven Assets, Making the Dollar the Prime Choice
In traditional frameworks, gold, long-term US Treasuries, the Swiss franc, and the Japanese yen are considered the four major safe-haven assets. However, the US-Iran conflict, coupled with energy supply shocks, forced the market to price both geopolitical and stagflation risks, rendering traditional safe-haven logic ineffective. Oil prices breaching $110/barrel reignited global inflation fears, suppressing the valuation of non-yielding assets. Simultaneously, concerns about expanded US defense spending worsening fiscal deficits and increasing bond supply pressures significantly weakened the safe-haven appeal of long-term Treasuries. In contrast, the relatively resilient US economy, combined with its anti-inflation advantage from energy independence, made the dollar a safe-haven asset offering both safety and yield, creating the unique divergence of a strong dollar alongside weak gold and weak Treasuries.
Rising Energy Prices Diverge Global Economies, Improving US Terms of Trade
From a balance of payments perspective, medium-to-long-term exchange rates are determined by a country's net foreign asset position and its terms of trade. The oil price surge created clear divergence among economies. As a major net energy exporter, the US saw its energy trade surplus expand directly, improving national income and the current account margin. Conversely, developed economies like the Eurozone and Japan, highly dependent on energy imports, faced a triple pressure of surging imported inflation, rising production costs, and shrinking trade surpluses, leading to a weakening fundamental backdrop. Global wealth was effectively transferred via energy trade from Eurasian importers to the US. This relative fundamental advantage widened interest rate differentials between the US and Europe/Japan, providing solid medium-term support for the dollar and explaining the broad-based weakness of non-dollar currencies during this crisis.
Fed Policy Expectation Reversal Drives Capital Inflows via Interest Rate Parity
Geopolitical conflict provided the emotional trigger for the dollar's short-term rebound, but the reversal in Fed policy expectations was the core driver of its sustained strength. Earlier in H1 2026, global markets uniformly bet on gradually receding US inflation, a moderating economy, and a Fed rate-cutting cycle in the second half, creating clear downward pressure on the dollar. Chair Warsh's arrival reconfigured the Fed's policy framework, significantly raising the bar for rate cuts, lowering inflation tolerance, and quickly heating up market expectations for hikes. According to interest rate parity theory, rising US Treasury yields widened the interest rate differential with other major economies, prompting sustained inflows of cross-border carry trade capital into the US, directly supporting the dollar's exchange rate from a flow perspective.
Paradigm Shift: Deep Changes in the Fed's Monetary Policy Framework Under Warsh
Chair Warsh, who formally took office in May 2026, unveiled a new set of monetary policy adjustments at his first FOMC meeting in June. This was not merely a minor rate tweak but a broad optimization of the communication mechanisms, policy objectives, and tool combinations from the Powell era, marking a formal departure from the "high transparency, strong forward guidance" model. The Fed entered a new Warsh-led era of "data-dependent, ambiguous communication." This policy paradigm reconstruction is reflected not only in the hawkish turn on rates but more profoundly in changes to the underlying logic of the Fed's framework.
The Warsh-era framework exhibits three core characteristics. First is a fundamental shift in the reserve system—from "ample reserves" to "scarce reserves." Warsh proposed using a combination of "balance sheet reduction + rate cuts," significantly shrinking the Fed's over $6 trillion balance sheet. The core of this strategy is to clear MBS holdings, return to a pure Treasury structure, and allow private markets to discover risk through price signals again, rather than relying on the Fed's administered rates. Second is a complete turn in communication philosophy. Warsh explicitly opposed the Powell-era strategy of exhaustive transparency, believing it severely undermined policy flexibility. The June policy statement was two-thirds shorter, deleting forward guidance and risk assessments, retaining only a single-objective commitment to "price stability." This Greenspan-esque opaque style aims to restore the Fed's institutional authority as a "price defender" rather than a market "soother." Third is a technical reconstruction of the inflation analysis framework. Warsh proposed shifting the monitoring focus from "core PCE" to "trimmed-mean PCE." While this adjustment provides potential theoretical support for future rate cuts, it risks underestimating inflation persistence, and internal Fed divisions on this remain.
The June meeting left the federal funds rate unchanged at 3.50%-3.75%, the fourth consecutive pause, but the overall dot plot was distinctly hawkish, with officials' expectations for a 2026 hike notably firmer. Economic projections showed a stagflationary tilt of lower growth and higher inflation, reflecting the Fed's heightened priority on combating persistent inflation. Warsh himself did not submit a dot plot forecast, downplaying its guidance value, while simultaneously establishing five specialized working groups to comprehensively review Fed communication, balance sheet policy, data usage, productivity and employment, and inflation analysis frameworks, pushing the central bank to return to its role as an independent policymaker rather than an expectation manager. With reduced policy certainty guidance, market pricing is shifting to pure data dependence, and elevated interest rate volatility will become the norm. Long-term challenges for Warsh's policies include multiple balancing acts: balance sheet reduction will reshape global liquidity and asset valuations while contending with external constraints like fiscal and geopolitical pressures. Key indicators to watch include the pace of reform implementation, the actual productivity boost from AI, and the interplay with government on the timing of rate cuts.
Safe-Haven Asset Divergence: The Underlying Logic of the Dollar's Outperformance
During the US-Iran conflict, the dollar's performance as a safe haven comprehensively outpaced the three traditional havens—gold, the yen, and US Treasuries—with significant price divergence. A comparative analysis of the pricing logic for these four assets helps deconstruct the core reasons for the dollar's outperformance.
The Dollar vs. Gold: Rising Real Rates Suppress Non-Yielding Asset Valuation
Gold, a non-yielding commodity, exhibits a strong negative correlation with US real interest rates. In this episode, geopolitical conflict pushed up inflation expectations, while Warsh's hawkish stance lifted nominal Treasury yields. The combined effect drove US real rates higher, increasing the opportunity cost of holding gold. Capital flowed out of gold and into yield-bearing dollar assets, resulting in the counterintuitive scenario of gold prices falling despite heightened geopolitical risk, confirming that real rates are the primary variable for gold pricing in a stagflationary environment.
The Dollar vs. the Yen: Energy Import Dependency Undermines the Yen's Safe-Haven Foundation
The yen has long served as a global funding currency for carry trades due to its low rates, while Japan's low external debt and stable current account have traditionally underpinned its safe-haven status. However, this energy crisis struck at Japan's economic weakness: its near 100% dependence on energy imports meant soaring oil prices drastically worsened its terms of trade and shrank its current account surplus, undermining its fundamental footing. Simultaneously, persistent monetary policy divergence between the US and Japan widened the interest rate differential, removing the incentive to unwind yen carry positions. The yen's safe-haven function failed entirely, offering no valuation hedge against the dollar.
The Dollar vs. US Treasuries: Fiscal Deficit Concerns Weaken Treasury's Safe-Haven Appeal
US Treasuries, as the global risk-free asset, have historically been the first port of call in a crisis. However, in this episode, Treasury prices fell (yields rose), primarily due to market expectations of expanding US fiscal deficits. Escalation in the Middle East was seen as likely forcing increased US defense spending, raising Treasury supply. Coupled with the high-interest-rate environment increasing debt servicing costs, this led markets to question US fiscal sustainability. This supply-side shock combined with fiscal risk undermined the inherent price stability of Treasuries, stripping them of their safe-haven allocation value. In summary, within the new macro environment of high rates, high inflation, and high volatility, the dollar possesses a unique risk-return advantage relative to other global safe havens, making its strength a logical outcome.
Outlook for the US Dollar Index in H2 2026
The dollar's trajectory in the second half will be jointly determined by three variables: the pace of geopolitical risk abatement, the slope of US inflation decline, and the implementation of Fed monetary policy. Based on current fundamental, policy, and geopolitical information, we discuss three scenarios: baseline, upside risk, and downside risk.
Baseline Scenario (70% Probability): Geopolitical Cooling and Falling Inflation Lead to a Weaker, Range-Bound Dollar
This is the most likely path. The core drivers are threefold. First, Middle East tensions gradually ease, a US-Iran ceasefire agreement is reached, Strait of Hormuz shipping fully resumes, oil supply risks dissipate, and oil prices decline, eroding the dollar's energy-related premium. Second, falling commodity prices lead to a steady decline in overall US inflation, easing Fed pressure and reigniting market bets on rate cuts by Q3 end. US Treasury yields peak and decline, marginally reducing the dollar's interest rate advantage. Third, the US's long-term structural twin deficits (fiscal and current account) return as a market focus, weighing on the dollar's long-term valuation. Overall, the dollar index is expected to maintain high levels before gradually correcting, supported initially by hawkish policy inertia but trending lower in the mid-to-late period as rate cut expectations build. The year-end range is projected at 96-99.
Upside Risk Scenario (20% Probability): Protracted Middle East Conflict Fuels Another Dollar Surge
If US-Iran negotiations completely break down, the Strait of Hormuz remains blocked long-term, and the global oil supply gap widens, international oil prices could exceed $120/barrel, reigniting global imported inflation. In this scenario, US inflation data surprises to the upside again, the Fed's hawkish stance intensifies further, potentially even restarting rate hikes. US Treasury yields would rise again, widening interest rate differentials. A combination of renewed geopolitical risk premium and fresh monetary tightening expectations would push the dollar index higher again. The target range would be 100-104. Key indicators to watch are daily Strait of Hormuz shipping data and US monthly CPI figures.
Downside Risk Scenario (10% Probability): High Rates Trigger a Hard Landing, Leading to a Deep Dollar Correction
If the Fed maintains high rates and continues balance sheet reduction, overly tight financial conditions could puncture US economic resilience. A rapid cooling of the labor market, sharply weaker non-farm payrolls, and a downturn in AI-related capital expenditure cycles could trigger a broad risk asset selloff. The Fed would then likely abandon its inflation fight to counter economic downturn risks, launching an aggressive rate-cutting cycle. Such a rapid policy reversal would completely undermine the dollar's interest rate support, and coupled with a reversal in the US's relative economic advantage, would lead to a deep correction in the dollar index. The target range would be 93-96. Key indicators to watch are US non-farm payrolls, unemployment rates, and earnings reports from major US tech firms.
Conclusion
The volatile performance of the US dollar index in the first half of 2026 serves as the most direct microcosm of a global macroeconomic paradigm shift. Global markets have entered a new macro cycle defined by high volatility, high uncertainty, and常态化 supply shocks. Under Chair Warsh, the Fed has broken with past conventions of transparent policy, seeking a new monetary policy anchor within ambiguity. The反复 Middle East geopolitical risks continue to test global market risk-pricing capabilities. For FX investors and global asset allocators, rather than attempting to pinpoint exact dollar index levels, the core investment logic is to adapt to this new macro paradigm, closely follow the rhythm of the Fed's policy framework changes, and monitor marginal shifts in geopolitical risk. In a market environment shrouded in global macroeconomic fog, firmly anchoring to the three core variables of fundamentals, policy, and geopolitics is essential for navigating the tides of dollar exchange rate fluctuations and identifying a clear investment direction.
Comments