From the last quarter of 2001 to the third quarter of 2005 the real price of oil increased by 103%. Such an increase is comparable to the one experienced during the oil shock of 1973. At the same time, the behaviour of real GDP growth, Consumer Price inflation (CPI inflation), GDP Deflator inflation, real wages and wage inflation in the U.S. in the 1970s was very different from the one exhibited in the 2000s. What can explain such a difference? Within a two-country framework where oil is used in production, two kinds of shocks are analyzed: (a) a reduction in oil supply, (b) a persistent increase in foreign productivity (as proxy for the experience of China in the last years). It is shown that, while the 1970s are consistent with a supply shock, the shock to foreign productivity generates dynamics close to the one observed in the 2000s.