The Evolution of U.S. Trade Balances: From Surpluses to Persistent Deficits Historically, the U.S. enjoyed trade surpluses post-WWII, but shifted to deficits in the 1970s amid rising global competition and oil imports. By the 1990s, deficits grew with economic booms increasing import demand. Processes involve macroeconomic identities: Deficits equal net foreign capital inflows, funding fiscal expansions or investments. Broader context includes globalization's role in job shifts across sectors, w