America’s anaemic exports may gain strength too. Millions of tonnes of petroleum products and chemicals are shipped out through the ports of Los Angeles and Long Beach each year. A strike sapped activity at both by more than 3% in the first quarter. With the dispute resolved, they are now exporting record amounts. The exchange rate may help. The dollar rose by almost 9% in trade-weighted terms in the second half of 2014, as the American economy strengthened, making exports more expensive for foreigners to buy. That run-up has since reversed, with the greenback down 2% since March.