Following its resounding success in the Gulf and Iraq wars, the M1 Abrams has established itself as one of the most successful tanks of all time. The M1 was originally developed in the early 1970s following the failure of the joint US-West German MBT-70 project which left the US in need of a successor to the venerable M60. Designed to counter the latest generation of Soviet armor, it was the first tank to feature the British-developed Chobham armor, a composite armor largely composed of ceramics which was superior to anything available at the time and which gave the M1 its characteristic angled turret shape. Later versions would be uparmored with depleted uranium making it by some accounts the best protected tank currently in service. Unlike most Russian tanks, the M1 did not traditionally use explosive reactive armor (ERA) or active protection systems though newer variants optimized for urban warfare can be equipped with ERA, slat armor, and some have adopted the Israeli-built Trophy APS system. Other elements of survivability such as blow-out panels for the ammunition compartment were also introduced. Following the trend send by the Soviet T-80, the M1 featured a gas turbine which gives the 65-ton vehicle outstanding speed and a large power-to-weight ratio, at the expense of heavy fuel consumption and considerable logistical and mechanical complexity needed to service it in the field. The M1 was originally designed with a US-built variant of the British L7 105-mm (the same as the M60), though it was later decided to upgun it with the Rheinmetall Rh-120 gun which is also standard on the Leopard 2. This is capable of firing a variety of US and NATO ammunition, including depleted uranium APFSDS rounds which are the standard in US service. The M1 was originally designed with a US-built variant of the British L7 105-mm (the same as the M60), though it was later decided to upgun it with the Rheinmetall 120-mm gun which is also standard on the Leopard 2. Unlike most tanks with a single anti-aircraft machine gun, the M1 has two, a 12.7-mm M2HB for the commander's station and a 7.62-mm M240 for the loader. The M1 was first put to the test in the 1991 Gulf War where nearly 2,000 served. None was lost to enemy action, being practically invulnerable to the Iraqi knocked-down T-72s which in turn were easily destroyed thanks to the M1's "Silver Bullet" M829A1 depleted uranium round (more modern versions of the round like the M829A4 are designed to defeat the most advanced Russian ERA). The story subsequently repeated itself during the Iraq War as the tank was tested even further in urban combat; some tanks have received a special Tank Urban Survival Kit (TUSK) to address vulnerabilities. Despite its superb performance, the M1 has had only modest export success compared with its NATO sales rival, the Leopard 2, most likely due to the additional costs that its gas turbine involves compared to a traditional diesel engine. The M1 is currently in service with the militaries of Australia, Kuwait, Iraq, Poland, Saudi Arabia, and Egypt which has received over 1,000 units. Egyptian M1s participated during the country's 2011 revolution, while Saudi M1s have also been active in the Yemen Civil War. The US has recently pledged a number of M1s to Ukraine which means they are likely to enter combat against Russian forces, their original intended enemy, for the first time sometime in 2023.

The XM1 program began in 1971 and prototypes from Chrysler and Detroit Diesel were tested out in 1976, with the former winning the contract of what became the M1. These featured the British 105-mm L7 rifled gun, the same fitted on the M60. Additional frontal armor was provided in the M1IP (Improved) but production soon switched to the M1A1 which was the first to be equipped with the now standard Rheinmetall 120-mm gun (produced locally as the M256). This also featured a new NBC system as well as numerous automotive and equipment upgrades, and was the main variant to serve in the 1991 Gulf War. Shortly thereafter, production began on the M1A2, which featured depleted uranium directly in the composite armor mix as well as a myriad of equipment and electronic upgrades, including GPS navigation as well as an inter-vehicle information system. Further development of the M1A2 has consisted on various System Enhancement Packages (SEP) beginning with the initial M1A2 SEP with improved thermal sight and next generation depleted uranium armor. This was followed by the M1A2 SEPv2 with a remote weapons station. The latest M1A2 SEPv3 adds additional network and datalink improvements, additional armor, and optional Trophy APS. Upgrades have also been made to M1A1s to bring them closer to M1A2 standards. Some of these received additional depleted uranium armor and were known as the M1A1HA (Heavy Armor), with the M1A1HA+ having second-generation DU armor. Further DU armor components were added to the M1A1HC (Heavy Common) while some were given digital upgrades as the M1A1D. The M1A1 AIM (Abrams Integrated Management) adds FLIR, a thermal sight for the machine gun, and additional situational awareness components. These upgrades plus third-generation DU armor was added to the M1A1SA (Situational Awareness) many of which have been exported but with the DU armor (which is banned for export) replaced by tungsten. The TUSK or Tank Urban Survival Kit is a field upgrade for urban combat which initially consisted of ERA and slat armor and more protection for the machine gun stations. The later TUSK II kit features newer ERA in a distinctive tile-like shape as well as a second M2HB machine gun on the mantlet. These kits can be installed on either M1A1 or M1A2 vehicles. Non-combat versions include the M104 Wolverine Heavy Assault Bridge (HAB), and the M1 ABV (Assault Breacher Vehicle) for use by the US Marines. The Korean K1 tank is based on the M1 and is described separately.