U.S. National Debt Exceeds 100% of GDP for the First Time Since World War II

The U.S. debt-to-GDP ratio reached about 119% post-World War II (in 1946) and gradually declined due to post-war economic growth and moderate inflation. The recent breach of 100% continues the rapid accumulation of debt following the pandemic stimulus in 2020, with significant deficits resulting from large expenditures and tax cuts during both the Trump and Biden administrations.
On the capital side, the U.S. Treasury continues to issue large amounts of national debt, which is absorbed by the Federal Reserve, foreign governments (such as Japan and China), and domestic institutional investors to cover interest, social security, defense, and stimulus spending. The motivation is to maintain high levels of government spending while delaying hard fiscal adjustments. Currently, annual interest payments exceed the defense budget, creating a snowball effect of debt.
Similar to Japan, which has maintained a debt-to-GDP ratio above 250% without a crisis, or several European countries during high debt periods, the U.S. is currently in a high debt plateau, testing long-term sustainability in the balance between economic growth rates and interest rates.
Essentially, this is a concentration of capital: the government uses the national debt market to concentrate global private capital and foreign exchange reserves for current spending and debt rollover. The mechanism involves locking in debt at low interest rates during low-rate periods, while in a higher interest rate environment, the interest burden inversely squeezes fiscal space, gradually shifting pricing power from economic growth drivers to creditors (especially foreign holders), increasing future monetary policy and fiscal adjustment pressures.