Volkswagen AG and other carmakers warned that trade tensions risk dragging the global economy into a recession as the fallout starts to hit consumers. The gloom of the U.S. and China’s tit-for-tat tariffs cast a shadow over the Frankfurt Auto Show this week, where carmakers were seeking to whip up interest in critical new electric models. The geopolitical volatility adds another layer of uncertainty to an industry in the midst of a radical overhaul as the end of the combustion-engine era looms. “We come now into a situation where this trade war is really influencing the mood of the customers, and it has the chance to really disrupt the world economy,” Volkswagen CEO Herbert Diess said in an interview with Bloomberg TV.