The Iran war has triggered fresh economic anxieties as investors grapple with unprecedented debt levels and fiscal challenges. After successive shocks from the pandemic, tariffs, and Ukraine, this latest conflict arrives when global sovereign debt is projected to exceed 100% of GDP by decade's end, according to IMF forecasts.

Unlike previous supply shocks since 1945, the current crisis is compounded by record peacetime debt levels and intensifying deficit bias. Harvard economist Jeffrey Frankel notes that US federal interest payments now exceed both defense and non-defense discretionary spending, with the 2026 bill estimated at 3.2% of GDP. Similar pressures burden other advanced economies.

The combination of military build-ups, demographic pressures, and political gridlock creates a perfect storm for investors. Research by Marzian and Trebesch shows that geopolitical shocks historically lead to lasting fiscal expansion, with societies choosing 'guns and butter' that drive up debt and spending. Without fiscal restraint, markets face mounting risks from debt monetization, fiscal dominance, and potential financial repression as central banks prioritize government financing over inflation control.