Public debt is often portrayed as a ticking time bomb. Governments that borrow too much, we are told, eventually face an inevitable reckoning. Yet history presents a more complicated picture. Some of the world’s most successful economies have carried enormous debt burdens for decades without collapsing, while others have suffered severe crises despite having far lower levels of debt. If debt alone determined a country’s fate, these outcomes should not be possible.
A government’s ability to live with debt depends on whether it can generate enough income to service its obligations, how much of that income is already consumed by interest payments, whether it controls the currency in which it borrows, how rapidly its economy is expanding, and whether lenders believe it will honour its promises. These forces often matter more than the debt figure itself.
History offers numerous examples of countries that faced seemingly similar debt burdens but experienced very different outcomes. Looking beyond the debt figures and examining the foundations supporting them helps explain why some debt mountains proved surprisingly manageable while others became the starting point of financial crisis.
Britain: The Pioneer That Survived
At the end of the Napoleonic Wars in 1815, Britain’s public debt stood at roughly £850 million, while its economy produced only about £350 million annually. In other words, debt exceeded 250% of GDP, one of the highest debt burdens ever recorded for a major economy. Yet Britain not only avoided default but went on to dominate the global economy for much of the nineteenth century.
One reason was its ability to generate revenue. The British government collected roughly £50–60 million annually through customs duties, excise taxes, and other sources. Although debt was around 15–17 times annual government revenue, investors trusted Britain’s tax system and believed the government could continue raising revenue when needed. Debt may have been enormous, but so was confidence in the state’s ability to service it.
The interest burden was substantial. Britain spent roughly £30 million annually on interest payments, amounting to nearly half of government revenue. Such a figure would alarm investors today. However, because British government bonds were regarded as exceptionally safe, borrowing costs remained relatively low and manageable.
Unlike modern governments, Britain operated under the gold standard. The pound was tied to gold, limiting the government’s ability to create money freely. Britain therefore lacked the monetary flexibility enjoyed by countries such as the modern United States. Yet despite this constraint, investors continued to lend because they trusted Britain’s institutions, finances, and long-term prospects.
Economic growth also played a decisive role. The Industrial Revolution transformed Britain through factories, railways, technological innovation, and expanding trade. Britain did not reduce its debt burden by dramatically repaying it. Instead, it gradually outgrew it. Over the course of the nineteenth century, economic growth caused the debt-to-GDP ratio to fall steadily from around 250% to roughly 25–30% before the First World War.
Britain’s vast empire provided an additional layer of confidence. While colonial revenues alone did not pay off Britain’s debts, the empire placed Britain at the centre of a global network of trade, resources, and commerce. Investors believed that such a diversified economic system made a sudden collapse in government revenue far less likely. Combined with the dominance of the Royal Navy and Britain’s position as the world’s leading financial centre, this reinforced its reputation as one of the safest borrowers in the world.
Britain’s experience shows that debt sustainability depends on far more than the size of the debt itself. Despite carrying debt above 250% of GDP and devoting nearly 50% of government revenue to interest payments, Britain avoided crisis because it combined strong revenue capacity, manageable borrowing costs, sustained economic growth, and exceptional investor confidence. The foundations supporting the debt proved more important than the debt itself.
The United States: The Giant Debtor
If Britain’s debt story demonstrated how a country could survive an extraordinary debt burden, the United States raises an even more intriguing question. How can a country owe more than $36 trillion, carry debt exceeding 120% of GDP, and still be considered one of the safest borrowers in the world?
The United States has not always been heavily indebted. Following the Second World War, federal debt reached roughly 119% of GDP in 1946, a level that many feared would become unsustainable. Yet over the following decades, the debt burden steadily declined, falling to around 31% of GDP by 1980. Remarkably, this was not achieved through massive debt repayment. Instead, strong economic growth, rising incomes, inflation, and population growth allowed the economy to expand much faster than the debt itself.
The picture today is very different. Federal debt has climbed from roughly 55% of GDP in 2000 to over 120% of GDP today, driven by tax cuts, rising entitlement spending, the Global Financial Crisis of 2008, and the enormous fiscal response to the COVID-19 pandemic. In absolute terms, debt has crossed $36 trillion, a figure larger than the entire annual output of most countries combined.
Despite this, the United States continues to enjoy exceptional revenue-generating capacity. Federal revenues currently exceed $5 trillion annually, making the U.S. government one of the largest collectors of tax revenue in the world. Investors believe that a large and diversified economy provides the government with substantial capacity to generate future income, even if political disagreements often complicate tax policy.
The interest burden, however, has begun attracting increasing attention. Annual net interest payments are approaching $1 trillion, meaning that roughly one out of every five dollars collected by the federal government is now used to pay interest on existing debt. While still manageable, this figure has risen sharply following the increase in interest rates since 2022. Unlike the post-2008 period, when near-zero interest rates kept borrowing costs low, the government now faces significantly higher refinancing costs.
The United States also possesses an advantage that few countries enjoy: it borrows almost entirely in its own currency. Unlike Greece, which depends on the euro, or many emerging economies that rely on foreign-currency borrowing, the United States issues debt primarily in dollars. Since the Federal Reserve ultimately controls the supply of dollars, the risk of an outright default due to a shortage of currency is extremely low. The greater risk is inflation rather than insolvency.
Economic growth has historically been America’s most powerful debt-management tool. Following the Second World War, strong productivity growth and rapid economic expansion dramatically reduced the debt burden without requiring large-scale debt repayment. Whether the United States can repeat that experience remains an open question. Growth today is slower, the population is ageing, and healthcare and pension obligations continue to rise.
Perhaps the most important pillar supporting American debt is investor confidence. The U.S. dollar remains the world’s dominant reserve currency, and U.S. Treasury securities are widely regarded as among the safest financial assets available. Central banks, pension funds, insurance companies, and investors around the world hold trillions of dollars in Treasury bonds. In times of global uncertainty, capital often flows into U.S. government debt rather than away from it.
This combination of strong revenues, monetary flexibility, economic scale, and exceptional investor confidence explains why the United States can sustain debt levels that might trigger crises elsewhere. Yet America’s experience also highlights an important lesson. High debt does not automatically lead to collapse, but even the world’s most trusted borrower cannot ignore rising interest costs forever. As debt grows, the challenge increasingly becomes not whether the United States can borrow, but how long it can continue doing so without placing an ever larger share of government revenue at the service of past borrowing.
Greece: When the Foundations Cracked
For much of the 2000s, Greece appeared to be a success story. The country joined the Eurozone in 2001, replacing the drachma with the euro. Membership in the single currency brought significant benefits. Investors believed that lending to Greece was now much safer because it was part of the European monetary union. As a result, borrowing costs fell sharply and the government gained access to cheap credit.
During the years that followed, Greece borrowed heavily to finance public spending, social programmes, and infrastructure projects. For a time, the arrangement appeared sustainable. Economic growth was reasonably strong, borrowing was inexpensive, and few investors worried about the country’s finances. By the mid-2000s, Greece was able to borrow at interest rates of around 4–5%, not far above those enjoyed by Germany.
The illusion began to unravel after the Global Financial Crisis of 2008. As investors looked more closely at government finances, concerns emerged about the size of Greece’s deficits and debt. By 2010, public debt had reached roughly 146% of GDP. While this was undoubtedly high, it was not unprecedented. Britain had once carried debt above 250% of GDP, and several advanced economies had managed similar burdens. Clearly, debt alone was not the problem.
One challenge was revenue generation. In the years leading up to the crisis, the Greek government collected revenues equivalent to roughly 38–39% of GDP. While this may appear substantial, tax evasion was widespread and tax collection remained relatively weak compared with many Northern European countries. Investors became increasingly concerned that the government would struggle to generate sufficient income to support a rapidly growing debt burden. Unlike countries with strong records of revenue collection, Greece’s future fiscal capacity was viewed with increasing scepticism.
The interest burden soon became the real threat. As confidence weakened, investors demanded higher returns for lending to Greece. What had once been cheap borrowing became extraordinarily expensive. By 2011, yields on Greek 10-year government bonds had surged above 30%. Annual interest payments rose to roughly 6–7% of GDP, placing enormous pressure on public finances. Rising borrowing costs worsened the fiscal outlook, which further undermined confidence, creating a vicious cycle that became increasingly difficult to escape.
Unlike Britain and the United States, Greece faced another critical limitation. Although its debt was denominated in euros, Greece did not control the euro. Monetary policy was determined by the European Central Bank rather than the Greek government. Before joining the Eurozone, Greece could theoretically have responded to a crisis by creating more of its own currency, though at the risk of inflation. After adopting the euro, that option disappeared. Greece needed euros to service its obligations but could not create them itself. When investors lost confidence, the country found itself with very few policy options.
Economic growth, which often helps countries outgrow their debt burdens, moved sharply in the opposite direction. Between 2008 and 2016, the Greek economy contracted by roughly 25%, one of the deepest economic downturns experienced by an advanced economy in modern history. Businesses closed, unemployment soared above 27%, incomes fell, and government revenues weakened. Debt remained large while the economy supporting it became significantly smaller.
Ultimately, the crisis became one of confidence. Investors who had once treated Greek bonds as relatively safe assets began doubting the government’s ability to honour its obligations. Borrowing costs soared, financial markets effectively closed to Greece, and the country required a series of bailout programmes from European institutions and the International Monetary Fund. By 2011, public debt had climbed to around 172% of GDP, eventually peaking near 180% of GDP in the years that followed.
Greece’s experience demonstrates that debt crises rarely occur because of debt levels alone. The country entered the crisis with weakening revenue capacity, rapidly rising interest costs, limited monetary flexibility, a collapsing economy, and falling investor confidence. Together, these factors transformed what initially appeared to be a manageable debt burden into one of the most severe sovereign debt crises of the modern era.
The Greek story also highlights a lesson that Britain and the United States never had to confront. A government may owe debt in a stable currency, but if it does not control that currency, its room for manoeuvre during a crisis can be dramatically reduced. In the end, Greece’s greatest weakness was not simply how much it owed, but how few options it had when confidence began to disappear.
Argentina: The Country That Lost Trust
If Britain’s story is about credibility and Greece’s story is about the dangers of losing monetary flexibility, Argentina’s story is ultimately about trust.
Over the past century, Argentina has experienced repeated cycles of borrowing, inflation, currency crises, and sovereign defaults. It has defaulted on its debt multiple times, including major defaults in 1982, 2001, 2014, and 2020. What makes Argentina particularly intriguing is that many of these crises occurred at debt levels far lower than those carried by Britain or modern-day Greece.
At the beginning of the twentieth century, Argentina was one of the world’s wealthiest countries. Around 1913, its income per person was among the highest in the world and comparable to many Western European nations. Yet over the following decades, recurring economic instability gradually weakened confidence in the country’s institutions and policies.
Unlike Greece, Argentina controls its own currency, the peso. In theory, this should provide greater flexibility during periods of stress. However, investors often prefer lending in U.S. dollars rather than pesos because they fear the peso will lose value. As a result, Argentina frequently accumulates debt denominated in a currency it cannot create. Argentina can print pesos, but it cannot print dollars. This distinction has been at the centre of many of its debt crises.
Argentina’s debt burden has fluctuated considerably. Before the massive 2001 default, public debt stood at roughly 50–65% of GDP. By comparison, Greece would later enter crisis at around 146% of GDP, while Britain once carried debt above 250% of GDP. Argentina’s problem was therefore not the absolute size of the debt but the market’s belief that the government might struggle to repay it.
Revenue generation has also been a recurring challenge. Government revenues typically amount to roughly 25–30% of GDP, broadly comparable to many middle-income countries. However, persistent fiscal deficits meant that spending repeatedly exceeded revenues. In several years, fiscal deficits exceeded 5% of GDP, forcing the government to rely heavily on borrowing.
The interest burden has often been severe. Because investors perceive Argentina as a risky borrower, they demand significantly higher returns than they do from countries with stronger reputations. During periods of crisis, Argentina has faced borrowing costs exceeding 10–15%, and at times has effectively been shut out of international capital markets altogether. Even when debt levels were moderate, high borrowing costs made the debt difficult to sustain.
Economic growth has been equally problematic. While Argentina possesses abundant agricultural land, significant energy resources, and a highly educated population, its economy has often alternated between periods of rapid expansion and severe contraction. The country experienced deep recessions in 2001–02, 2018–20, and again struggled with instability thereafter. Economic volatility repeatedly undermined government revenues and investor confidence.
Inflation has become perhaps the most visible symptom of Argentina’s economic problems. In recent years, annual inflation exceeded 100%, and during 2023 it surged above 200%. At such levels, households rush to convert savings into dollars, businesses struggle to plan for the future, and confidence in the national currency deteriorates. The peso’s weakness further encourages reliance on dollar borrowing, reinforcing one of the country’s core vulnerabilities.
Ultimately, Argentina’s debt story is best understood through the lens of investor confidence. Britain maintained investor trust despite debt exceeding 250% of GDP. The United States continues to borrow heavily because investors believe in the strength of its institutions and currency. Greece lost confidence rapidly during the Eurozone crisis. Argentina, however, has struggled to rebuild confidence after losing it repeatedly over many decades.
This lack of confidence creates a vicious cycle. Investors demand higher interest rates because they fear future problems. Higher interest rates worsen the government’s finances. Weaker finances reinforce investor concerns. The cycle then repeats itself.
Today, Argentina’s public debt is roughly 75–85% of GDP. This is far below the debt burdens Britain carried after the Napoleonic Wars and World War II, and well below the levels reached by Greece during the Eurozone debt crisis. Yet investors remain cautious.
The Foundation Beneath the Debt
Revenue can be increased, economies can grow, currencies can be managed, and debts can be refinanced. Yet all of these ultimately depend on something less tangible: the willingness of lenders to believe that today’s promises will still be honoured tomorrow. Once that belief weakens, borrowing becomes more expensive, options become more limited, and even manageable debts can become a source of instability.
In the end, public debt is as much a question of credibility as it is of economics. Governments may borrow in different currencies, face different interest rates, and carry vastly different debt burdens, but their long-term success rests on a common foundation: maintaining the confidence that allows debt to remain sustainable in the first place.