Can America Afford $40 Trillion in Debt? What Investors Need to Know

By The Intelligence Edge Research Team · June 16, 2026 · 24 min read

US national debt has now crossed $39 trillion. We unpack who really owns it, if America can go bankrupt, and what to watch next.

US national debt has crossed $39 trillion. Here's how it got here, who actually holds it, and the three scenarios investors should be watching for.

Can America Afford This? Our Direct Answer

We believe the United States can comfortably service $39 trillion in debt today. The federal government has not missed a payment, Treasury auctions continue to clear without difficulty, and the dollar remains the dominant currency for global trade and reserves. In that narrow sense, the alarmist framing — "America is broke" — is wrong, and we think investors who trade on that framing alone are mispricing the present.

But we also think the comfortable framing — "debt doesn't matter for a country that prints its own currency" — is incomplete, and increasingly so. The arithmetic that matters isn't the $39 trillion headline number. It's the rate of change: how fast the debt is growing, how much it costs to service, and how that cost compares to everything else the government needs to fund. On those measures, the trend has shifted meaningfully over the past five years, and we analysed the data behind that shift below.

Our view, stated plainly: the United States is not in a debt crisis. It is in a slow-burning fiscal squeeze — one that is most visible not in the size of the debt itself, but in what the interest on that debt is starting to crowd out. That distinction matters for how investors should think about Treasury yields, the dollar, and fiscal policy risk over the next decade.

1. How America Got to $40 Trillion

The number itself can feel abstract, so we think it's worth tracing how the US arrived here — because the shape of the curve tells you more than the level.

For most of the postwar period, US federal debt was a manageable fraction of the economy — in the 1970s and early 1980s, debt held by the public sat well below 40% of GDP. From there, three distinct waves of borrowing reshaped the trajectory: the 1980s–2000s buildup driven by tax cuts, defense spending and recessions; the 2008 financial crisis, whose bank rescues, stimulus, and lost tax revenue roughly doubled the debt-to-GDP ratio over the following decade; and COVID-19, which produced the sharpest single jump in US fiscal history, pushing debt-to-GDP to roughly 133% in mid-2020 — a level not seen since the years immediately following World War II.

As of June 10, 2026, total public debt outstanding stood at $39.213 trillion — split between $31.592 trillion held by the public and $7.621 trillion in intragovernmental holdings. The debt-to-GDP ratio has settled at roughly 123%, and CBO's baseline has debt held by the public rising from 101% of GDP this year toward 120% by 2036.

The pace of accumulation is itself notable: over the twelve months to early March 2026, gross debt rose by $2.64 trillion — an average of roughly $7.2 billion per day. We think the key takeaway from this history isn't any single number — it's that each crisis ratchets the baseline higher, and the baseline has never meaningfully come back down. That pattern is the backdrop for everything that follows.

2. Interest Expense: The Real Problem

If there is one section of this article we'd ask investors to read carefully, it's this one. We believe the size of the debt is less important than what it now costs — and that cost has crossed a threshold that changes the conversation.

CBO's February 2026 baseline puts net interest costs at approximately $1.0 trillion in FY2026 — equivalent to 3.3% of GDP. That figure now exceeds the entire projected defense budget ($885 billion) and the entire Medicaid budget ($708 billion) for the same fiscal year. Interest on the debt is no longer a footnote — it is one of the largest line items in the federal budget, and it is growing faster than any other major category.

Why this is happening — and why it's structural, not cyclical

Two forces are compounding. First, the debt itself keeps growing as the government runs deficits — CBO projects a $1.9 trillion deficit in FY2026, equal to roughly 5.8% of GDP. Second, the cost of that debt has risen sharply. The average interest rate on the total marketable national debt was 3.355% as of February 2026 — up from just 1.512% five years earlier. As older, low-rate debt issued during 2020–2021 matures and gets refinanced at today's higher rates (the 10-year Treasury yield has traded around 4.4%–4.5% through June 2026), the average cost of the entire debt stock rises — even if the deficit itself stayed flat.

Where this goes if nothing changes

CBO's projections show net interest costs roughly doubling from $1.0 trillion in FY2026 to $2.1 trillion by FY2036 — rising from about 14% of total federal spending today to nearly 19% by 2036, and from 3.3% of GDP to 4.6% of GDP. Extended further, interest spending is projected to reach 6.9% of GDP by 2056 — at which point interest payments would exceed all defense spending and all discretionary spending combined, every year, indefinitely.

It does not mean the government "can't pay." It means that every dollar spent servicing existing debt is a dollar that isn't available for anything else.

We believe this crowding-out dynamic is the single most important fiscal trend for investors to track over the next decade, because it shapes the political incentives around tax policy, deficit reduction, and — most relevant to markets — how much new debt the Treasury needs to issue, and at what yield it can clear.

3. Who Owns America's Debt

This is the section we think is most misunderstood — and most likely to surprise readers who've absorbed the "China owns America" narrative.

Of the $39.2 trillion total, 80% ($31.6 trillion) is "debt held by the public" — the economically meaningful measure. The remaining 20% ($7.6 trillion) is intragovernmental debt — money the government owes its own trust funds, primarily Social Security and Medicare.

Within debt held by the public, domestic holders dominate. The Federal Reserve is the single largest holder of US debt overall, at approximately $4.9 trillion, built up through successive rounds of quantitative easing. Beyond the Fed, roughly 70% of publicly held debt is owned domestically — by mutual funds, pension funds, insurance companies, banks, and state and local governments.

Foreign entities hold roughly $9.4–9.5 trillion — about 24% of total debt. Japan is the largest foreign holder at roughly $1.1–1.2 trillion, having held that position since overtaking China in 2019. The United Kingdom is second at roughly $780–900 billion — much of it private financial-sector holdings routed through London. China's holdings have been steadily declining for over a decade, from a 2013 peak of roughly $1.3 trillion to approximately $650–760 billion today — around 2.4% of publicly held US debt.

We think the practical implication is this: the popular framing that foreign governments — particularly China — hold meaningful leverage over US fiscal policy through Treasury holdings is, on the current numbers, overstated. The far larger exposure sits with the Federal Reserve and with US-based pension funds, mutual funds, and insurers — meaning a disorderly Treasury market would be primarily a domestic financial stability event before it became a geopolitical one.

4. Can the US Actually Go Bankrupt?

This is the question that generates the most heat and the least precision in public debate, so we want to be careful with our language.

A sovereign currency issuer is not a household. A household that borrows must eventually repay principal from income, or it defaults. The US government borrows in its own currency and can — and routinely does — roll over maturing debt indefinitely by issuing new debt to replace it. It has never needed to "pay down" the national debt to zero, and there is no economic requirement that it ever should. As far as it goes, we agree with this argument.

But "can't default in the technical sense" is not the same as "no consequences." We see three distinct risk channels:

The dollar's reserve-currency status is a privilege, not a guarantee

Because the dollar is the world's primary reserve and trade-settlement currency, global demand for Treasuries provides a persistent buyer base most countries don't have. This is the core reason the US can run deficits that would be unthinkable for other nations. But this privilege has historically been earned through perceived fiscal and institutional stability — and we believe it can erode gradually rather than disappear suddenly.

Credit rating actions are a real signal of that erosion

In May 2025, Moody's downgraded the US sovereign credit rating from AAA to Aa1 — the first downgrade by Moody's since 1917 — following S&P's earlier downgrade to AA+. Neither triggered a crisis; demand at auctions held up. But we read these downgrades as data points in a trend, not isolated events — rating agencies explicitly cited long-term fiscal sustainability concerns, precisely the interest-expense trajectory detailed above.

The international comparison is more nuanced than it looks

Japan's government debt-to-GDP ratio sits at roughly 230–237% — nearly double the US figure — and Japan has sustained this for over two decades without a crisis. This is often used to argue the US has enormous headroom. We think this comparison is only partially useful. Japan's debt is overwhelmingly held domestically, Japanese households are large net savers, and — until very recently — Japanese interest rates were near zero. Even so, 2026 has seen Japanese government bond yields surge to multi-decade highs on spending concerns — a live illustration that even a debt structure considered "safer" than America's is not immune to repricing once rates normalize. The lesson we take from Japan isn't "the US has room to spare" — it's that debt-to-GDP alone is a poor predictor of when markets reprice sovereign risk, and the transition can happen faster than the accumulation that preceded it.

Our synthesis

We do not believe a conventional US default is a meaningful near-term risk, and we think investors positioning for one are fighting the wrong battle. The more realistic risk is what some economists call fiscal dominance: a state where debt service costs become large enough to constrain policy choices, where higher Treasury issuance pressures yields independent of Fed policy, and where the "risk-free rate" embeds a small but rising fiscal risk premium. That is a gradual repricing, not a default — but it shows up first in Treasury yields, then the dollar, then equity valuations through the discount rate. We think this is already partially underway.

5. Three Scenarios for the Next Decade

We want to commit to calibrated views, not hedge everything into vagueness. Each scenario below carries a probability band (likely = 55–80%, roughly even chance = 45–55%, unlikely = 20–45%, very unlikely = 5–20%) and a confidence level: 🟢 high confidence (multiple corroborating sources, few load-bearing assumptions) or 🟡 moderate confidence (reasonable evidence, but leaning on at least one unverified assumption).

6. What Investors Should Watch

Rather than trying to time a crisis we believe is more likely to arrive gradually than suddenly, we think a short watchlist is more useful — each of which we plan to track in upcoming pieces in this series.

1. Net interest as a share of federal outlays. Currently around 14% (FY2026), with CBO projecting ~19% by 2036. A sustained move materially above that glide path is the clearest signal Scenario 1 is deteriorating toward Scenario 3.
2. Treasury auction demand — bid-to-cover ratios. Recent readings around 2.3–2.9 indicate healthy demand. A sustained drop below 2.0 on benchmark maturities would be an early warning.
3. 10-year and 30-year Treasury yields. Currently around 4.4–4.5% and roughly 5.0% respectively. The level matters less than the reason for any sharp move.
4. Foreign holder behavior via TIC data. Watch for acceleration in China's gradual reduction, or — more importantly — any change in Japan's position, given Japan's own fiscal pressures are intensifying in parallel.
5. Credit rating actions and their market reception. Further downgrades are likely over time; what matters is whether markets continue absorbing them calmly or start reacting more sharply.
6. The debt-to-GDP ratio itself, but as a trend, not a threshold. There's no magic number that triggers a crisis — the rate of change relative to GDP growth determines whether the situation is stabilizing or deteriorating.