The M1 Abrams were 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 M1A2C and D (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. The Abrams was due to be replaced by the Future Combat Systems XM1202 but due to its cancellation, the U.S. military has opted to continue maintaining and operating the M1 series for the foreseeable future by upgrading with improved optics, armor, and firepower.

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