Just Because Lockheed Says They Can Build A Mach 6 Jet Doesn't Mean We Need One

Extreme speed is once again becoming a prized quality at the Pentagon after a two decade long hiatus following the retirement of the SR-71 Blackbird . Now Lockheed says it can build 3,800 MPH proof-of-concept jet in just a couple of years time, an aircraft that could lead to an fully operational "SR-72." Amazing as that sounds, does the Air Force even need such an aircraft at all?