US President Donald Trump often tweets from his iPhone about pressuring China to address its $375bn trade surplus with the United States. But a closer look at the Apple smartphone reveals how the headline figure is distorted. The big trade imbalance - at the heart of a potential trade war, with Trump expected to impose tariffs on Chinese imports this week - exists in large part because of electrical goods and tech, the biggest US import item from China. Apple Inc's iPhone, however, illustrates how a big portion of that imbalance is due to imports of American-branded products - many of which use global suppliers for parts, but are put together in China and shipped around the world. Take a look at the iPhone X. IHS Markit estimates its components cost a total of $370.25.

The trade deficit had narrowed in the spring as exports of U.S. computer products and farm goods rose. U.S. exporters benefited from a decline in the value of the dollar, which makes American products cheaper overseas. Solid global growth also helped, as economies from Europe to Asia to Latin America are expanding simultaneously. Exports in June were the highest in 2 ½ years.