Why does a factory closing in China raise prices at a store in Ohio?
Background
International trade is not a separate branch of macroeconomics -- it is wired into every domestic outcome. Exchange rates affect inflation. Capital flows affect interest rates. Trade policy affects employment patterns and supply chain resilience.
The open-economy dimension also constrains domestic policy. Monetary expansion under flexible exchange rates works partly through depreciation, which helps exports but raises import prices. Under fixed exchange rates, monetary independence is sacrificed entirely.
What it covers
The current account records trade in goods and services plus net income and transfer flows. The capital and financial account records cross-border investment: foreign direct investment, portfolio flows, and reserve changes. By construction, the two accounts must sum to zero.
A current account deficit means the country imports more than it exports and finances the gap with capital inflows -- either foreign investment or borrowing. Whether that deficit is a problem depends on what the borrowed capital is used for, the sustainability of the financing, and the exchange rate regime.
Open question
Is the trade balance reflecting comparative advantage and efficient capital allocation, or is it signaling an unsustainable external position that will eventually require painful adjustment?