Why is the M1 Abrams Tank so feared Russia

The M1 Abrams is a third-generation American main battle tank designed by Chrysler Defense and named for General Creighton Abrams. It was officially standardized as TANK, COMBAT, FULL TRACKED, 105MM, M1 ABRAMS on June 15, 1978. The M1 Abrams was developed from the failure of the MBT-70 project to replace the obsolescent M60 tank. There are three main operational Abrams versions, the M1, M1A1, and M1A2, with each new iteration seeing improvements in armament, protection, and electronics. Extensive improvements have been implemented to the latest formerly designated M1A2 System Enhancement Package version 3 or SEPv3 and M1A2 SEPv4, respectively versions such as improved composite armor, better optics, digital systems and ammunition.