The problem started before World War I. The gold standard was working fairly well. But it broke down because of the war and what happened in the 1920s. And then the U.S. started to become so dominant in the world, with the dollar becoming the central currency after the 1930s, the whole world economy shifted.

The U.S. berates China for its exchange rate policy, which Washington doesn't like. But one-sided pressure on China to change its exchange rate is misplaced.

The price of gold was fixed at $35 an ounce in 1934, but by the time the U.S. got through the Korean War, the Vietnam war, with all the associated secular inflation, the price level had gone up nearly three times.

Robert Mundell Quotes