The US Dollar Index staged a modest technical rebound to the 99.00 level during early European trading on Wednesday, following a period of sustained weakness. However, the greenback remains in a fragile market environment, with US fiscal policy, Federal Reserve rate expectations, and upcoming inflation data collectively determining the next directional move.

The US Treasury Department has expanded its long-dated debt buyback program, raising the maximum size of each operation from $2 billion to at least $4 billion. The primary objective is to improve liquidity in the long-end Treasury market and alleviate rising long-term funding costs. Market participants view this measure as a short-term stabilizer for longer-dated yields, but it has also intensified scrutiny of America's fiscal position. With total US government debt surpassing $40 trillion, the buyback program primarily addresses bond market supply-demand dynamics rather than resolving the underlying fiscal deficit and debt growth concerns.

Traders are also monitoring whether the Treasury might tap cash balances held in its general account to fund the expanded buybacks. Should this operation scale further, it could reduce supply pressure in the long-end market and put downward pressure on longer-dated yields. For the dollar, lower Treasury yields diminish the interest rate appeal of US assets. Therefore, while the buyback initiative aims to stabilize the bond market, it may inadvertently weigh on the greenback in the near term.

Meanwhile, Fed rate expectations have shifted notably. Earlier this month, markets heavily priced in a September rate hike, but cooling inflation data and a reassessment of the economic outlook have driven the implied probability of a 25-basis-point hike down to roughly 38.4%, a significant drop from around 67% at the start of the month. This rapid repricing of rate expectations is a key reason why the Dollar Index has struggled to sustain any meaningful rebound.

Attention now turns to the upcoming US July PCE price index, a critical inflation gauge for the Fed. If core inflation continues to moderate, markets could further reduce expectations for higher US rates, exerting renewed downward pressure on the Dollar Index. Conversely, a hotter-than-expected reading could lift Treasury yields and provide temporary support for the dollar.

Markets are also awaiting policy signals from the Jackson Hole symposium. Remarks from Fed Chair Kevin Warsh could serve as a major catalyst for near-term dollar direction. If the tone emphasizes inflation risks and a prolonged period of elevated rates, Treasury yields may bounce, potentially allowing the Dollar Index to retest the 100 handle. However, a dovish tilt would likely extend the dollar's current weakness.

From a policy communication standpoint, markets require more than just rate guidance; they are seeking clearer direction on US fiscal policy. Analysts suggest that without a more defined fiscal consolidation plan from the Treasury and a clearer Fed policy framework, the dollar's recent rebound may prove unsustainable.

Geopolitical risks are providing some safe-haven support for the dollar. Recent expansions of economic sanctions against Iran could drive capital flows back into traditional safe-haven assets like the greenback if regional tensions escalate. However, this support is more dependent on shifts in risk sentiment than on improvements in the dollar's fundamental outlook, leaving its durability in question.

Across the global FX landscape, the dollar faces broad-based pressure. Declining long-term US rate expectations erode the yield advantage, while shifting policy expectations in major economies such as Europe and Japan could further influence capital allocation across currencies. Should the Dollar Index remain persistently below 100, markets may gradually form a consensus on medium-term dollar weakness.

On the daily chart, the Dollar Index maintains a bearish short-term bias, trading consistently below the 100-day moving average and the mid-Bollinger Band, indicating that medium-term sellers retain control. Despite the recent bounce from lows, the index faces resistance near the 99.00 level. The first resistance sits at the mid-Bollinger Band around 99.55, followed by the 100-day moving average near 99.70. A decisive break above 99.70 would open the door toward the upper Bollinger Band around 100.40. Only a reclaim of the 100 handle would meaningfully improve the dollar's medium-term bearish structure.

To the downside, the lower Bollinger Band near 98.65 represents the most critical near-term support. A confirmed break below this level could see the index extend toward 98.20 and potentially 97.80. The RSI currently reads approximately 34.60, approaching oversold territory, suggesting that while bearish pressure persists, limited room for immediate downside may exist due to technical correction needs. Therefore, if PCE data comes in soft, the Dollar Index may first breach 98.65 before entering a new bottoming phase; a stronger reading could leverage the oversold condition to fuel a quicker rebound.

On the 4-hour timeframe, the Dollar Index is at a critical confirmation stage following its rebound from lows. The 99.00 level serves as the near-term bull-bear divide. A break above 99.55 with sustained momentum could strengthen the rebound, targeting 99.70 and then 100.00. Conversely, failure near 99.55 followed by a drop back below 98.65 would signal that sellers have regained control, potentially resuming the downtrend. The current technical structure remains bearish, with the 99.55-99.70 zone acting as the core resistance band determining whether this rebound can strengthen.

In summary, the dollar's current rebound appears more like a technical correction within a weak structure than a definitive trend reversal. The Treasury's expanded long-dated buyback program may ease pressure on longer-term yields but fails to address the root causes of US debt and fiscal deficits, potentially undermining the dollar's interest rate support by depressing long-end yields. In the near term, the July PCE data and Jackson Hole policy signals will dictate the dollar's next direction. If inflation continues to cool and the Fed strikes a dovish tone, the risk of a break below 98.65 rises. If PCE shows renewed inflation stickiness and the Fed signals a more hawkish stance, the dollar could challenge 99.70 and even the 100 handle. Overall, unless the Dollar Index can reclaim 100 decisively, markets should treat the current rebound as a corrective move within a medium-term downtrend. Key watchpoints include the interplay between US inflation, long-end Treasury yields, fiscal policy, and Fed communication, which will ultimately determine whether the dollar can escape its current weak structure.