The Dow tumbled more than 1,000 points on Tuesday after gasoline prices spiked overnight and oil rocketed above $83 a barrel as the widening conflict in Iran began to disrupt global energy supplies. The Dow Jones Industrial Average plunged 1,050 points, or 2.01%, while the S&P 500 fell 1.80%, or 138 points, and the Nasdaq Composite dropped more than 450 points, or 1.96% as investors dumped stocks amid surging oil prices and escalating tensions tied to the Iran conflict.Oil prices surged as traders priced in ...