When U.S. markets watched Paris metaphorically implode in recent weeks, the consensus reaction among investors was blunt: "Let's not do that."

The unrest that swept through the French capital began with protests highlighting failings in the public school system, then snowballed into a wider expression of dissatisfaction with the cost of living and job prospects.

The economic backdrop is strained. Unemployment stood at 8.3% in the second quarter, real GDP growth was 0.4%, and national wage growth came in at 1.7%. Underpinning it all is public debt, currently at 116% of GDP, with 30-year bond yields topping 5.4% at the time of writing. The debt-to-GDP ratio—total government borrowing measured against the size of the economy—is a standard gauge of a country's fiscal position, and long-dated bond yields represent the interest investors demand to hold a government's debt for decades.

The U.S. bond market—where policymakers have also drawn criticism for presiding over mounting debt—stalled as the French turmoil unfolded. In fact, 10- and 30-year Treasury yields even declined.

"There's a reason that the U.S. has pulled back a little bit in the last few weeks [and] why France has not," Heather Long, chief economist at Navy Federal Credit Union, told a Bipartisan Policy Center (BPC) event last week. "It's a couple of key indicators that differentiate us from France and suggest … that we still have a little bit of room to have these debates now, in the context of a K-shaped economy."

"We're at about 100% debt-to-GDP; they're at 120% debt-to-GDP," she continued. "They are further along that crisis curve, and they are growing at about 0.5%. We're growing at just over 2%. That's a pretty big difference."

The "K-shaped" label describes an economy splitting along diverging paths—some groups pulling ahead while others fall behind—rather than rising or falling together.

While economists largely agree that policymakers may be naive in hoping to simply grow the U.S. out of a debt crisis, starting from a point of strength rather than stagnation gives the economy a better chance of rebalancing its debt-to-GDP ratio. The arithmetic works in a government's favor when growth outpaces borrowing: the denominator expands, easing the ratio even if the debt balance itself never falls.

Long added that France also differs from the U.S. in that the former has exhausted much of its revenue-generating capacity through taxes. Per the OECD's most recent data, the "tax wedge"—the difference between labor costs to the employer and the corresponding net take-home pay of the employee—for French workers is 47.2%. The U.S., by comparison, sits at 30%.

"It's certainly not easy to raise taxation in the U.S., but from a financial world perspective and the bond market perspective, there's a lot more room to experiment and to grow in the United States than there is in France," Long added. "To me, the biggest warning sign from France is really not just the K-shaped economy effect, but the generational effect that's going on and to see young people really driving this latest protest … from the disparities that they're seeing generationally, and that seems like a pretty big foreshadowing [of] what we could see here as we creep towards 120% debt to GDP."

The generation question

As with any debt, the question of repayment is not if but when—and that is the question budget experts are asking the public and politicians to think about.

Phil Swagel, director of the nonpartisan Congressional Budget Office—the federal scorekeeper that produces the budget projections and cost estimates Congress relies on—said policymakers face a series of choices: how to prepare for growth to slow if spending is cut, which forms of tax to explore, and more.

"The other set of choices that you can think about with the deficit is about which generation is paying, so the longer we wait to make changes, that means some generations are … missing out on their share of the burden of the adjustment," Swagel told the BPC event, "and then who within each generation will pay a tax."

He explained: "The longer we wait means some generations, in some sense, don't share in the burden of the adjustment. Then, who within each generation is affected? I think there's a societal consensus it will be progressive, not in the political sense, but in the sense that households with relatively high lifetime incomes will have more of a share of the adjustment. But that's a societal preference, and there's lots of room for disagreement in there."

Until those choices land, the gauges Long and Swagel pointed to—relative growth rates, the debt-to-GDP path toward the 120% mark, and what bond markets charge to lend governments money over the long term—remain the running scoreboard for how the U.S. and France compare.

This story was originally featured on Fortune.com.