A Belgian Wealth Manager Explains Why It Thinks US Treasuries Aren’t a Sustainable Bet

The post-World War II architecture of global finance has long positioned US Treasuries as the ultimate safe haven—the bedrock upon which institutional portfolios are built. Yet a $60 billion Belgian wealth management firm's two-decade rejection of this conventional wisdom signals a broader reassessment underway among sophisticated European investors grappling with structural imbalances in American fiscal policy. This contrarian stance, while unconventional, reflects mounting concerns about the sustainability of US debt trajectories. With federal deficits persistently exceeding $1 trillion annually and the debt-to-GDP ratio hovering near 120%, the mathematics of indefinite Treasury accumulation grow increasingly problematic. For European portfolio managers accustomed to disciplined fiscal governance—particularly in Northern Europe—the trajectory appears unsustainable. The Belgian firm's strategy illuminates a critical tension facing European investors. While US Treasuries offer nominal safety and deep liquidity, their real returns have compressed significantly. Negative real yields (after inflation adjustment) have become commonplace, particularly at shorter maturities. For wealth managers pursuing genuine capital preservation rather than mere accounting exercises, this represents a structural deterioration in risk-adjusted returns that warrant portfolio recalibration. The implications extend beyond theoretical debates about fiscal sustainability. European institutional investors—pension funds, insurance companies, and private wealth managers—have historically maintained substantial Treasury allocations as portfolio anchors.