When the US national debt crossed $40 trillion, it ceased to be a mere statistic and became a force of gravity, bending bond markets, currencies, and policy priorities across Asia. Officials in Tokyo understand this dynamic intimately, having spent decades wrestling with their own debt-laden equilibrium. Japan's experience offers a cautionary tale of what happens when a government's borrowing needs begin to steer global capital flows rather than the other way around.
It is one thing for this dynamic to unfold in Asia's second-largest economy, but quite another when it involves the world's largest economy and the guardian of the reserve currency. The irony is that central banks and investors spent the first half of 2026 piling into dollars as a safe haven amid the Iran war, despite the US having initiated the conflict alongside Israel in late February. Global funds raced into hyper-liquid US Treasuries, but cracks are now appearing.
Last week, US 30-year Treasury yields surged to their highest level since 2007, reaching 5.3%. This prompted Treasury Secretary Scott Bessent's team to declare war on bond bears. Bessent rolled out a Treasury debt buyback program to cap surging yields, ostensibly modeled after the policies of Nobel laureate James Tobin during the Kennedy administration in the 1960s. However, the move has serious Japanese echoes—and not good ones.
Japan's lost decades as a warning
The narrative quickly shifted from Bessent bending markets to the "bond vigilantes" handing the US Treasury its comeuppance. Famed investor Stanley Druckenmiller took to the Wall Street Journal to slam Bessent's gamble, warning that "governments defending prices against fundamentals always lose." Japan is Exhibit A. Since the late 1990s, successive Japanese governments and Bank of Japan (BOJ) teams have declared war on bond bears. By 1999, the BOJ had slashed official rates to zero, and in 2001, Tokyo pioneered quantitative easing. Since then, Japan has unleashed countless financial sorties to battle investors bidding bond yields higher.
In 2013, the BOJ supersized its balance sheet, gorging on Japanese government bonds (JGBs) and stocks until its balance sheet topped the nation's $4.2 trillion economy. In 2016, it experimented with yield-curve-control (YCC) tactics, introduced quantitative and qualitative monetary easing (QQE), and intensified its negative interest rate policy (NIRP) to keep JGB yields under wraps. These tactics have been a short-term success but a long-term disaster. They helped Tokyo avoid the meltdown that traders had long bet on—the JGB "widowmaker" trade that burned investors like Kyle Bass of Hayman Capital and David Einhorn of Greenlight Capital.
However, Japan's financial excesses and shrinking population problems have worsened exponentially. In May 2025, then-Prime Minister Shigeru Ishiba said Tokyo's deteriorating finances were "worse than Greece," a remark that resonated with observers. Ishiba was trying to dissuade lawmakers from cutting taxes to boost GDP yet again, warning that continued fiscal stimulus might draw credit rating agencies' attention to Tokyo's precarious finances. Last year, Japan's population recorded its steepest fall on record—the fifth straight annual decline. The combination of runaway debt, dismal demographics, and government fiscal stimulus to combat sluggish growth tends to raise alarm bells among credit rating agencies.
Bessent clearly wants to avoid that fate. In the short run, the worry at Treasury headquarters is about the $1.2 trillion of US Treasuries that Japan owns as the biggest holder. Last month's joint Japan-US yen intervention was largely about eliminating incentives for Tokyo to dump dollars. The longer-term play here seems to ignore the lessons from Japan's lost decades. One lesson is that papering over cracks in the bond market is no substitute for slowing debt growth, never mind the scale of the overall debt load. Since January 2025, the Trump administration has devised no plans to reduce a debt-to-GDP ratio that's now approaching 225%.
There are big questions about whether Bessent sent the wrong signals with his bond twist. Robin Brooks, an economist at the Brookings Institution, says the reason markets are having such a violent reaction is that "they're extremely attuned to the risk that high-debt governments start fiddling with interest rates." Brooks adds that "after all, if investors don't get paid adequate risk premia, why would they hold your government bonds? Instead, they'll head for the exit, putting pressure on the currency. Markets have watched Japan closely and learned from it. They're on the lookout for signs of anything similar happening elsewhere. The buyback announcement—as long-term Treasury yields were making multi-decade highs—therefore understandably got a big reaction."
The other group Bessent risks trolling is Washington's top bankers, who could turn against US government debt. In recent years, China, America's No. 2 financier in Asia, has been advising banks to cut their exposure to US government securities. And perhaps Japan, too. As Richard Michelfelder, an economist at Rutgers University, says, recent market intervention efforts "help keep US rates down. Japan holds many hundreds of millions of dollars in US Treasury bonds. If they have to sell some to buy yen, that will come back to bite us." Paolo Pasquariello, a finance professor at the University of Michigan, told ABC News that "a perfect storm is motivating Japan to seek a stronger yen." The other side of the coin: a stronger yen is benefiting Japanese consumers and companies, but it also complicates the US Treasury's efforts to manage its debt.
The parallels between Bessent's gambit and Japan's debt trap are hard to ignore. As Japan's bond market stress signals deeper global fiscal strains, the US risks repeating Tokyo's mistakes. The US-Japan yen intervention masks a deeper fiscal tug of war, and the US debt hitting $40 trillion has sparked partisan blame but little substantive action. Whether Bessent's bond buyback will be a short-term fix or a long-term disaster remains to be seen, but history suggests that fighting the bond market is a losing battle.
