A global debt crisis in the making?

A global sovereign debt adjustment has begun in Japan and is testing other major borrowers. This note argues that quasi-QE interventions may contain yields temporarily, while sovereign issuance and AI funding crowd out the wider economy. Three Axioma Risk scenarios examine managed, contested and failed intervention scenarios. 
 

If governments set the curve and hyperscalers set the spread, everyone else gets the bill.

Executive summary

Long-dated government bond yields are rising across major developed markets. The conventional interpretation is that term premium has returned as an investable source of carry. A less comfortable interpretation is that investors are rationing scarce balance-sheet capacity. Governments must refinance a growing stock of debt while funding current expenditures. Hyperscalers must finance an AI infrastructure buildout whose capital requirements are beginning to outrun internal cash generation. Both borrower groups are large, recurring and less responsive to price than the ordinary corporate sector.

The sovereign adjustment is no longer theoretical. Japan is testing how far authorities can manage long-term yields through central-bank support, debt-management policy and greater reliance on domestic institutional demand. The United States is using buybacks, issuance management and verbal intervention to lean against pressure at the long end. These measures may stabilize market functioning, but they do not correct the fiscal arithmetic.

Three scenarios describe the path. The base case is a managed adjustment in which intervention succeeds but crowding out slows growth. The middle case is a contested adjustment in which intervention works intermittently and recession exposes mispricing in lower-quality credit. The hard case is failed intervention, in which investors exchange duration for liquidity.

What the bond market is telling us

Recent Bank of England, Bank of International Settlements (BIS) and The International Monetary Fund (IMF) research points to the same conclusion: long-term sovereign yields increasingly respond to fiscal and supply considerations rather than simply revised expectations for growth or central-bank policy.

The Bank of England finds that debt issuance surprises affect yields through duration-risk and local-supply channels. The BIS finds that fiscal-risk shocks steepen sovereign curves, lift inflation expectations, weaken currencies and depress equity prices. The IMF reports that global public debt rose to nearly 94 percent of GDP in 2025 and is projected to reach 100 percent by 2029, while rising interest burdens and leveraged non-bank participation increase repricing risk.

Investors are demanding greater compensation because future supply is larger, fiscal adjustment is politically uncertain and central banks are no longer automatic buyers of duration. Rising term premium can therefore be read not only as carry, but as a price signal attached to deteriorating fiscal arithmetic. 

The second pressure 
Sovereigns require funding because of past spending. Hyperscalers require funding because of future spending and investors are being asked to finance both at the same time.

The Bank of England evidence provides the mechanical link between fiscal policy and the curve. Joyce and Lengyel show that issuance surprises affect long-term yields through both aggregate duration risk and local supply, with larger effects when markets are already under stress. Their results imply that quantitative tightening and additional sovereign issuance are not separate influences: both increase the duration private investors must absorb.

The BIS evidence broadens the argument beyond one market. Gorea, Ng and Zampolli recover country-specific fiscal-risk shocks from sovereign and safe corporate bond yields across 12 economies. Those shocks generate stagflationary dynamics, steepen sovereign curves, depreciate currencies and lower equity prices, with stronger effects when monetary policy remains accommodative or sovereign premia are already elevated. Fiscal risk can therefore tighten financial conditions even before conventional credit losses appear.

The IMF places those market signals in a global balance-sheet context. Public debt is rising while governments face spending demands linked to defense, demographics, strategic autonomy and climate transition. Interest expense is increasing as old debt is refinanced at current yields, while leveraged non-bank intermediaries have become more important holders and traders of sovereign securities. The issue is not simply whether debt is sustainable over decades, but whether markets can absorb the path of issuance without repeated repricing events.

Together, the three strands shift the interpretation of rising term premium. A larger premium may compensate investors for duration and inflation uncertainty, but it can also reveal doubts about fiscal governance, market liquidity and the authorities’ willingness to allow an unconstrained clearing price. That is why the rise in long yields should be treated as a warning signal rather than automatically classified as an investment opportunity. 

Japan shows how the adjustment begins

Japan is not facing imminent default or conventional loss of market access. It is facing a problem of market clearing at politically acceptable yields. The government must fund an exceptionally large debt stock while the Bank of Japan attempts to normalize policy and reduce its dominant role in the JGB market.

The response combines market support and managed demand. The Bank of Japan has slowed the reduction of JGB purchases, while the government has encouraged domestic pension institutions to invest more in Japanese assets. This resembles a mixture of debt management, financial repression and potential fiscal dominance. None eliminates the risk premium; each merely changes who is required to hold it.

The policy choices distribute the cost differently. Renewed Bank of Japan purchases place more duration on the central-bank balance sheet and risk subordinating monetary normalization to fiscal stability. Encouraging pension funds or insurers to buy more JGBs redirects household savings toward the state and can constrain the institutions’ asset-allocation objectives. Shortening issuance reduces duration supply today but raises the frequency at which the debt stock must be refinanced.

Once the long yield is politically managed, the exchange rate becomes the market’s complaint department. Investors unable to extract full compensation in long JGBs can instead sell the yen. The currency weakness is therefore not separate from the debt problem. It is one of the channels through which investors mark down the credibility of a funding regime that asks them to absorb fiscal risk without being fully paid for it.

Japan therefore represents an early, managed phase of a debt crisis rather than a conventional default event. The stress appears in the authorities’ growing need to influence who buys long debt and at what price. Market access remains open, but the market-clearing yield is becoming politically and fiscally consequential.

The United States is testing its own tools

In August 2026, the Treasury announced that it would at least double the maximum size of liquidity-support buybacks in the 10- to 20-year and 20- to 30-year sectors, from USD 2 billion to at least USD 4 billion per operation. The transactions are officially intended to improve liquidity in off-the-run securities. They also reduce the amount of long duration the market must warehouse and signal that Treasury is willing to lean against pressure at the long end. Treasury officials also indicated that the Treasury General Account, or TGA, could be used to help fund the larger purchases, giving the operation a much larger implied balance sheet than the stated buyback caps alone suggest and weigh on investors’ decision whether to test the Treasury’s resolve. That matters because the message to investors is not only that Treasury is buying long bonds today, but that it may have more firepower available if the market decides to test the long end.

Buybacks are not QE in the strict monetary-policy sense. Treasury cannot create reserves, and the aggregate funding requirement does not disappear. But the market effect is uncomfortably QE-like. Treasury retires the bond it buys, injects cash into the system and removes off-the-run duration from private balance sheets. If those bonds had been used as collateral, sellers may then need to replace them with newer Treasuries. The operation therefore does more than improve liquidity. It retires old debt, nudges investors toward new issuance and changes the maturity and collateral composition of the market. The liability is not extinguished. It is recycled into a more convenient form. 

Quantitative Tightening (QT) in name, Quantitative Easing (QE) in effect

The macroeconomic backdrop still argues for quantitative tightening. Inflation remains uncomfortable, employment and economic activity has been resilient, and central banks need to restore room on their balance sheets. The policy prescription should therefore be straightforward: reduce official demand and allow private investors to set the price of duration.

The political and fiscal response points in the opposite direction. Japan has slowed the reduction of JGB purchases and encouraged domestic institutions to invest more in Japanese assets. The United States is buying back long-duration debt while continuing to fund a large borrowing requirement. Governments are not formally restarting QE. They are reproducing parts of its market effect through slower QT, long-bond buybacks, maturity transformation and managed institutional demand.

The mechanisms are not equivalent. Central-bank purchases create reserves. Treasury buybacks alter the maturity and liquidity profile of public debt. Pension and insurer purchases redirect regulated savings toward the state. Greater bill issuance reduces current duration supply but raises rollover exposure. Although the legal labels differ, the shared objective is to prevent long-term yields from reaching the level required by an unconstrained market.

Authorities want private investors to absorb more government debt because central banks are conducting QT, but they do not want to pay the term premium required to persuade investors to do so. In effect, they are asking for private-sector price discovery only at a politically acceptable price. 

Different but the same   
Central banks are supposed to be reducing sovereign-bond holdings. Governments are using slower runoff, buybacks, maturity transformation and managed institutional demand to limit the rise in long yields. Although the labels differ, the duration effect is increasingly similar. 

The fiscal cliff is becoming a funding loop

A larger debt stock must be refinanced at higher coupons. Higher interest expense widens future deficits. Wider deficits require more issuance. More issuance places additional duration into a market from which central banks are withdrawing. The funding requirement begins to generate part of the next funding requirement. Rinse and repeat.

Governments cannot decline to refinance maturing debt because the clearing yield is inconvenient. Investors can wait while issuers cannot. In a free market, that is called a lenders’ market: lenders set the price, not borrowers. In sovereign debt, that price appears as term premium. It is the extra compensation investors require for absorbing duration, fiscal uncertainty and liquidity risk when the issuer’s need to borrow is less flexible than the market’s willingness to lend.

The loop runs through maturity as well as volume. Issuing more bills can suppress current term premium by removing duration from the market, but it also shortens the government’s refinancing horizon and increases sensitivity to future policy rates. Lengthening maturity protects the budget from near-term refinancing risk, but requires investors to accept more duration at today’s clearing yield. Debt managers can choose where the risk resides, but they cannot make it disappear.

Auction behavior therefore becomes a useful measure of investor discipline. Larger tails, repeated concessions, weaker indirect demand and greater reliance on shorter maturities indicate that investors are setting more demanding terms. Governments may still fund themselves, but doing so at a progressively higher all-in cost converts market pressure into future fiscal pressure.

Hyperscalers are becoming marginal borrowers in credit

The AI buildout requires data centers, semiconductors, power generation, transmission, cooling and network capacity. Capital expenditure is rising faster than free cash flow for parts of the hyperscaler complex, increasing the use of bonds, loans, leases, securitization and private credit.

Hyperscalers are not price-insensitive. They are less price-sensitive than most companies because strategic competition rewards speed and capacity. Their scale and strong ratings allow them to issue at spreads and all-in funding costs that would force weaker borrowers to step back. The strongest borrowers can therefore raise the financing hurdle for everyone else. 

The price of scarce capital 
Governments influence the risk-free curve. Hyperscalers influence the spread demanded above it and the ordinary borrower pays both. 

The pressure extends beyond public bonds. Data-center finance draws on bank lending, private credit, asset-backed markets, leases and long-duration institutional capital. Those pools overlap with the investors and intermediaries needed to absorb sovereign issuance. The common constraint is balance-sheet capacity.

A weaker corporate borrower therefore competes with two preferred borrowers: a government that must refinance and a hyperscaler that has strategic reasons to keep building. Neither is likely to reduce funding demand quickly when yields rise. The marginal manufacturer, property developer, utility or services company adjusts first by canceling investment, reducing hiring or accepting less favorable financing terms.

This is crowding out without an official credit-control regime. Governments raise the price of duration, hyperscalers help set the relative-value hurdle in investment-grade credit, and other borrowers pay both. The recessionary impulse can therefore begin before defaults rise or high-yield spreads widen materially.

This time may actually be different

During the 2010 to 2012 euro-area crisis, punishment was selective. Investors sold weaker sovereigns and moved into Bunds, Dutch debt or Treasuries. The present episode is broader. Long-end yields have risen across the United States, United Kingdom, France, Germany and Japan. Investors are not merely repricing one issuer against a clean benchmark. They are questioning the benchmark set itself.

The signal has moved from relative credit risk to the absolute price of duration. Because the least-bad long bond can still lose money, investors facing a liquidity event may prefer cash, overnight instruments and very short-dated bills. Gold remains the clearest non-sovereign debasement hedge, but it cannot fully replace the liquidity function of government bonds.

The parallels remain important. Investors punished weak fiscal fundamentals then and can do so now. In both episodes, sovereign stress migrated into institutions holding government debt, while official intervention tested the boundary between market discipline and central-bank support. The difference is the availability of substitutes.

Research on safe assets shows that Treasuries and Bunds benefit from unusually inelastic demand, but substitution patterns narrow during stress. Bunds are primarily substitutable within a relatively small euro-area safe-asset set, while Treasuries connect to a broader global market. If several benchmark issuers are repriced simultaneously, the system can become short of assets that are deep, liquid, duration-bearing and unquestionably safe at the same time.

Gold…and what else can be used to hedge?  

The answer depends on the shock. During an immediate liquidity event, investors are likely to prefer cash, deposits, overnight instruments and very short-dated bills. These remain sovereign claims, but they contain little duration and can meet collateral needs. The escape is therefore not necessarily from governments; it is from long-term promises into near-term liquidity.

Gold is the clearest non-sovereign candidate for a slower loss of confidence in fiscal and monetary discipline because it carries no issuer credit risk. Its usefulness is nevertheless conditional. Gold is volatile, yields nothing and can be sold during the first stage of a margin-driven liquidation. It is a store-of-value allocation, not a complete substitute for the transactional and collateral functions of government bonds.

The Swiss franc can serve as a relative fiscal and currency hedge, subject to intervention by the Swiss National Bank. Highly rated supranational and agency debt can reduce exposure to one national treasury, although those markets are too small to absorb a wholesale retreat from major sovereign securities. Inflation-linked bonds hedge realized inflation but remain liabilities of the same government and offer limited protection against a pure liquidity shock.

Bitcoin belongs in the debasement narrative but not yet in the core safe-haven allocation. Its supply rule is independent of governments, which gives it long-horizon appeal, but its observed behavior remains closer to a volatile risk asset when liquidity is scarce. It may hedge distrust over time, but it is not a dependable source of cash during a margin call.

There may therefore be no single successor to the Bund or Treasury safe haven. The defensive allocation fragments by function: bills and cash for liquidity, gold for issuer and currency debasement risk, selected currencies for relative fiscal quality, and supranational paper for high-grade income. That fragmentation is itself evidence that the financial system has become less efficient and more fragile.

When the risk-free rate sends the first warning

Most credit crises begin in high yield and end with demand for sovereign bonds. The current sequence appears reversed. The first persistent warning is coming from long-dated sovereign debt while high-yield spreads remain unusually tight.

High-yield spreads are measured against government curves. If the reference yield rises first, part of the tightening appears in the benchmark rather than in the spread. Credit may not be disagreeing with the warning; it may simply be late.

The inversion 
The supposedly risk-free component is registering the warning while the risky component continues to collect the coupon. 

Several structural features can postpone the response in public high yield. The index is of better average quality and shorter duration than in past cycles. Elevated all-in yields attract income buyers even when spreads provide limited compensation. Issuers that refinanced early can delay the maturity wall, while weaker borrowers increasingly use private credit, amend-and-extend transactions or liability-management exercises rather than default immediately in public markets.

The benchmark also matters. A corporate yield equals a sovereign reference curve plus a credit spread. If the first tightening occurs in the sovereign curve, the all-in borrowing cost can rise materially while the spread appears calm. Investors may even prefer short-duration credit carry to long sovereign duration when the perceived source of risk is fiscal policy itself.

The apparent inversion is therefore plausible rather than contradictory. Sovereign markets can identify a deterioration in the cost and availability of duration before recession weakens corporate cash flows. High-yield spreads then become the confirmation signal rather than the initial warning.

Three scenarios for the adjustment

The scenarios represent stages in a potential escalation, distinguished primarily by whether official intervention remains credible and effective.

What would confirm or challenge the thesis?

The cleanest confirmation would be long yields rising while long-run inflation expectations remain comparatively stable. That is broadly the current signal: long bond yields and term premia have risen, while forward inflation expectations have remained relatively stable. Investors appear to believe that hawkish central banks can still bring inflation back toward target over time. The concern is that politics may prevent them from doing the job cleanly. In that case, rising term premium is not an inflation forecast. It is a credibility charge for fiscal interference, policy uncertainty and the risk that central banks are forced to choose between price stability and sovereign-funding stability.

Other warnings include repeated auction concessions, weaker bid-to-cover ratios, declining indirect-bidder participation, greater reliance on short-dated issuance, rising repo volatility and wider investment-grade new-issue concessions. An increase in cross-country correlation among developed sovereign curves would be especially important because it reduces the diversification benefit available during stress.

The real-economy test is whether policy easing reaches borrowers. If central banks cut rates while bank lending standards, corporate yields and project hurdle rates remain high, the curve and the spread have taken control of transmission. Falling non-AI capital expenditure, weaker hiring and rising downgrade activity would indicate that crowding out is moving from markets into growth.

The thesis would be challenged if fiscal consolidation reduced expected issuance, central banks completed QT without higher term premia, hyperscaler funding returned to internal cash generation, and long yields fell alongside stable market liquidity. It would also be weakened if high-yield spreads widened first while long sovereign bonds resumed their traditional safe-haven role.

Investment implications

Portfolio analysis should stress sovereign curves and credit spreads together. The global scenario should reduce assumed diversification across developed sovereigns and include deterioration in market liquidity, collateral conditions and stock-bond correlation.

The managed case argues for liquidity and recognition that policy success can still crowd out economic growth. The contested case requires recession and downgrade sensitivity. The failed-intervention case requires planning for collateral, cash access and a positive stock-bond correlation.

The stress-testing implication is that sovereign and credit shocks should not be treated independently. The managed scenario requires a curve-steepening shock combined with modest spread widening and weaker growth assets. The contested scenario requires a two-stage path in which long yields rise before policy rates fall, while credit spreads widen as recession arrives. The failed-intervention scenario requires simultaneous sovereign selloffs, reduced cross-country diversification, repo stress, wider bid-ask costs and positive stock-bond correlation.

Liquidity assumptions deserve the same attention as price shocks. A portfolio can appear protected by gold, short-duration credit or government bonds under closing-price scenarios while remaining vulnerable to margin calls, wider haircuts or delayed settlement. Full revaluation in Axioma Risk should therefore be supplemented with explicit assumptions for collateral, financing costs and the speed at which defensive assets can be monetized.

The framework also separates hedge functions. Cash and bills protect immediate liquidity, gold addresses long-horizon debasement and issuer risk, currencies express relative fiscal confidence, and supranational debt provides high-grade income with less direct national exposure. No single asset should be assumed to replace every function previously provided by long-dated sovereign bonds.

Conclusion: from managed market to market discipline

The global sovereign-debt adjustment is no longer theoretical. Japan is testing how far authorities can manage long yields through central-bank support, debt management and domestic institutional demand. The United States is using its own tools to lean against pressure at the long end. These interventions may succeed, but success should not be confused with resolution.

The defining contradiction is that authorities want QT without the higher term premium required to make QT possible. Neither Japan nor the United States has formally returned to QE, but both are discovering how difficult it is to leave.

In the managed case, authorities contain disorderly yields and crowding out weakens growth. In the contested case, intervention buys time but recession exposes credit mispricing. In the failed-intervention case, investors reinterpret official action as evidence that the unconstrained clearing yield is fiscally intolerable. At that point, the flight to quality becomes a flight to liquidity.

A global debt crisis has not yet become a global liquidity crisis, but Japan suggests that the first stage is already under way. The hard case begins when investors decide that time is precisely what governments are trying to borrow.

Bottom line 
If governments set the curve and hyperscalers set the spread, everyone else gets the bill. If investors stop trusting authorities to manage either, they will exchange duration for liquidity and leave governments to discover the market-clearing price on their own.