GDP, i.e. everything produced and spent in a country is GDP=C+I+G+(X-M), where C is consumer spending, I is private sector investment, G is government expenditure, and (X-M) is the difference between exports (X) and imports (M). So, having a balance of trade deficit is not necessarily a problem if e.g. inward investment compensates. If you focus on the balance of trade you just get public policy that is over-focused on the needs of exporting companies, to the detriment of consumers and investors.