Key point: Washington always tries to have the best weapons. But even the finest tanks must be constantly upgraded to avoid falling behind.
In the 1970s, the situation for NATO tank forces in Europe was grim. The program to develop the next generation battle tank for both Germany and the United States, the MBT-70, was about to crumble and fail, and the next generation of Soviet tanks was about to reach the front lines.
The tank forces of the U.S. and its allies were reliant on the aging M60 tank or roughly comparable analogues. Declassified CIA documents from the period shared a pessimistic estimate of the balance of forces: the Soviet tanks were more numerous and technically superior.
Following the failure of the MBT-70, Congress forced the Army to begin a new tank program under strict cost and time limitations. A developmental concept paper (DCP) for this new tank was created in 1972 and approved in 1973. The DCP called for competitive evaluations, trialing of turbine versus diesel engines and concurrent operational and engineering trials.
The armor and armament of the new tank, now dubbed the XM1, aimed to incorporate the latest developments in armor technology. The Army specified that the British-developed Chobham armor be incorporated into the design.
The next-generation British 110mm tank gun and German 120mm tank gun were also considered for incorporation on the XM1. However, the German gun was found to have some difficulties in development when the XM1 program was about to finish. As a result, the XM1 had provision to mount the 120mm in its trunnion design but mounted the 105mm M68A1 that armed the M60 Patton.