The U.S. Department of Defense has launched a massive review of consulting services contracts, with an eye toward making cuts.Investors are concerned about the implications for the companies providing those services. Shares of Booz Allen Hamilton (BAH -0.67%) and Science Applications International (SAIC -4.83%) both traded down as much as 5% on Friday, and shares of Leidos Holdings (LDOS -2.47%) and General Dynamics (GD -1.21%) were off 4% and 2%, respectively, though Booz and General Dynamics made back som ...