Government bond yields are spiking around the world: U.S. Treasuries, Japanese JGBs, and United Kingdom gilts are hitting highs not seen in decades. All pale in comparison to France.

Since January, yields on France's 10-year sovereigns have risen by more than that of any other G-7 country, from 3.5% to around 4.90% today. That is the 10-year's highest yield since 2002 and roughly 140 basis points above the German equivalent -- the widest spread between those sovereigns since the 2010 euro zone crisis. (A basis point is 1/100th of a percentage point.) Meanwhile, France's 30-year sovereign yield is pushing toward 5.5%, the product of a perfect storm of unsustainable public finances, political dysfunction, and stagnant economic growth.

This disorder recalls the year 2010, when a Greek sovereign-debt meltdown triggered a wider financial crisis across the euro zone, roiling the global economy and markets. Today, France has $4 trillion in public debt, roughly eight times Greece's 2010 debt in today's prices. It is teetering on the cusp of a full-blown debt crisis, which would not only roil markets, but also draw sharp attention to other countries' unsustainable debt paths, including the U.S., Japan, Italy, and the U.K.

Much like those countries, France's public finances are only getting worse. An independent report commissioned by the French finance ministry estimates that, under current policies, the deficit will rise from 5.4% of gross domestic product today to 6.8% by 2030.

Political dysfunction makes near-term deficit reduction nearly impossible. President Emmanuel Macron has cycled through numerous prime ministers while trying to curb public spending, which stands at an extraordinary 57% of GDP. Faced with a deeply divided legislature, he has been unable to build a consensus on putting France's finances on a sustainable course.

That probably won't change soon. The immediate barrier to political movement on the spending issue is less the protests raging across the country right now -- students and unions are demanding more government spending on education and public services -- and more so the country's coming presidential election.

The leading candidates have little appetite for proposing unpopular spending cuts or tax increases ahead of the vote in April. In fact, they are proposing measures that would deepen the country's fiscal problem. The favorite to win, far-right Marine Le Pen, is campaigning on promises to lower the retirement age from 64 to as low as 60 and to cut value-added taxes on energy and essential goods. On the far left, Jean-Luc Mélenchon proposes to cancel roughly 18% of the national debt held by France's central bank.

Even if Le Pen or Mélenchon wanted to pursue a more responsible budget policy, it isn't clear either would have the votes in the National Assembly to enact it. Snap elections for the Assembly will occur several weeks after the presidential vote. We shouldn't rule out the possibility that the legislative boy will remain as polarized and unable to agree on fiscal fixes as it is today.

Macroeconomic forces are working against France, too. A series of shocks are hitting its sclerotic economy, including a surge in energy prices due to the Iran war, sharply higher borrowing costs as investors grow concerned about France's public finances, and a wave of Chinese exports flooding the European market. With France's economy already growing by less than 1% a year, those shocks could tip the economy into a recession.

For Americans who remember the 2010 euro zone crisis, the lesson is that a full-blown debt crisis in France is unlikely to stay confined to that country. On the contrary, it would shine a bright, painful light on America's own fiscal problems. The U.S. government's debt load recently surpassed $40 trillion and, without major corrections, its annual budget deficit will exceed $2 trillion for years to come. Paying back that debt is getting pricier: The all-important 10-year Treasury yield surpassed 5.3% for the first time since 2002.

Asked about rising Treasury yields this week, Treasury Secretary Scott Bessent dismissed the issue. "It is a global phenomenon," he said.

Rising U.S. Treasury yields are different from the rising European bond yields, according to Bessent. Unlike Europe, rising Treasury yields are the product of strong growth. He then predicted the 10-year Treasury yield will go down after the Iran war. He did so by seeming to turn a blind eye to our government's massive borrowing requirement and the waning foreign appetite for our government's bonds.

Some more reliably good news is that the European Central Bank likely won't let France fail for fear of the euro unraveling, and it is better equipped than in 2010 to deal with debt crises, with new tools like the Transmission Protection Instrument. But this shouldn't breed complacency in Paris: The ECB will buy large quantities of French bonds only if French leadership commits to a credible macroeconomic adjustment program. The ECB will also need buy-in from Germany, its largest shareholder, which won't be easy, with the far-right, anti-euro Alternative for Germany party on the march.

Americans should hope France's bond market troubles are as a wake-up call for Washington to get its fiscal house in order, and spare us from a government bond market crisis of our own.

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Desmond Lachman is a senior fellow at the American Enterprise Institute. He was a deputy director in the International Monetary Fund's Policy Development and Review Department and the chief emerging market economic strategist at Salomon Smith Barney.