An Upgraded Abrams Tank Is Not The Answer

A General Dynamics cheerleader is arguing that:

The Army is expected to make an initial determination on the Abrams’ successor next year. Rather than building an entirely new tank, like the Decisive Lethality Platform [PDF], the Army should continue along the Abrams’ iterative design route and purchase the Abrams X with the goal of the first production unit being in the hands of Army soldiers this decade. . . . 

the Abrams X will boast a number of improvements over the current M1A2 while being built around the tried and true Abrams chassis. Compared to the M1A2, the Abrams X is simply more mobile. Its lighter frame allows it to weigh in at 10 tons less and its new hybrid diesel electric engine makes the tank 50 percent more fuel efficient. That new engine also allows for “silent watch” functionality, letting soldiers operate weapons and sensors without the tank giving off its usual thermal or acoustic signatures. Along with hardware, the Abrams X will also feature upgraded software, including AI systems that can identify targets and compile them in a ranked list for human operators to eliminate. . . . 

instead of the Abrams X, the Army is currently considering the Decisive Lethality Platform as a follow-on to the Abrams. A notional, possibly unmanned platform contained within the Next Generation Combat Vehicle (NGCV) program, the DLP may cost significantly more than a manned tank because of the sophisticated control and communication systems required due to a lack of crew. Besides the years, and possibly decades, needed to bring the DLP from R&D to production at scale, it would undoubtedly cost billions in R&D funding. Already, the estimated lifecycle costs [PDF] for two other vehicles within the NGCV program, Mobile Protected Firepower (MPF) and the planned replacement for the M-2 Bradley, the Optionally Manned Fighting Vehicle (OMFV), stand at $62 billion in fiscal 2019 dollars or nearly $72 billion today. For just the OMFV’s R&D cost [PDF] in the coming fiscal year, the Army requested over $589 million, with $3.5 billion planned between FY21 and FY27. In contrast, since the Abrams X is essentially an upgrade, it would only cost close to $650 million in R&D costs, the amount spent on the SEPv3.

The main argument for the Abrams X is that going in a new direction will take too long and carry too many technology risks. But, this advocate sees the problem and blindly refuses to acknowledge it:

Despite the calls of those sounding the death knell of the tank due to the war in Ukraine, the platform is far from dead. Tanks will remain relevant into the future as a way to rapidly punch through enemy lines while wielding large amounts of firepower to eliminate a host of obstacles, whether that be vehicles, infantry, or other tanks.

Simply put, this isn't true. Tanks have been mostly irrelevant on the war in Ukraine which has been the best real world example of how conventional warfare between near peers works today. Abrams tanks were too heavy and unwieldy to be of much use in Kosovo, Afghanistan, or Iraq as well. 

They filled a need that other systems met better and were too vulnerable to anti-tank missiles and land mines. Infantry, motorcycle troops, armored personnel carriers, robot tanks, drones, helicopters, guided artillery missiles, fixed wing aircraft, and land mines (including large IEDs) are all very effective at destroying tanks from outside the range of their main guns. Their main 120mm gun's range of about 2.5 km is less than the range of a typical modern anti-tank missile of about 3.5 km to 10 km. Its anti-personnel rounds have a range of 600 meters. Its bunker breaching rounds have a range of 500 meters to 2 km. An Abrams tank has nothing to defend itself against a helicopter gunship, fixed wing close air support attack fighter, or armed aerial drone.

During the Iraq War invasion, at least nine Abrams tanks were put out of action by fire from mere rocket-propelled grenades. In urban areas in Iraq, "some crews were also issued M136 AT4 shoulder-fired anti-tank weapons under the assumption that they might have to engage heavy armor in tight urban areas where the main gun could not be brought to bear." About 80 Abrams tanks used by the U.S. military were lost in the first two years of the conflict to enemy fire despite the fact that all of Iraq's tanks and artillery were obliterated in the early days of the conflict. Afterwards:

Between 2010 and 2012 the U.S. supplied 140 refurbished M1A1 Abrams tanks to Iraq. In mid-2014, they saw action when the Islamic State of Iraq and the Levant launched the June 2014 Northern Iraq offensive. During three months, about one-third of the Iraqi Army's M1 tanks had been damaged or destroyed by ISIL and some were captured by opposing forces. By December 2014, the Iraqi Army only had about 40 operational Abrams left. . . .

Tanks had limited utility in Afghanistan due to the mountainous terrain.

At least twenty Abrams tanks deployed by Saudi Arabia in the war in Yemen have been destroyed so far, despite the fact that the Yemeni forces it has engaged are not even "near peer" forces by U.S. military standards. Saudi Arabia has purchased about 440 Abrams tanks although it isn't clear how many have been deployed in Yemen.

They are too heavy (even with a 10 ton weight reduction from its current 74 tons leaving it still the heaviest tank in the world still in service, other than older Abrams tanks) to cross many non-U.S. bridges. They are also so heavy that not many of them can be deployed in the critical first days of a war (only a C-17 or C-5 can transport them, the C-5 requires a decent commercial grade airport and can only take 2 tanks per sortie, a C-17 requires a field grade airstrip and one of them can be transported per cargo plane sortie):

The limited capacity (two combat-ready tanks in a C-5, one combat-ready tank in a C-17) caused serious logistical problems when deploying the tanks for the first Persian Gulf War, though there was enough time for 1,848 tanks to be transported by ship.

They have a long logistics tail due to their fuel hungry engines even with a 50% improvement in fuel efficiency (each one would need about 400 gallons of fuel per 300 miles), that have to be met with completely unarmored fuel trucks.

Since they are twelve feet wide, they aren't good in tight quarters like narrow non-U.S. streets and mountain passes. They are also slow. At 42 miles per hour on road and 25 miles per hour off road nothing about them is "rapid" and they hold back the advance of other military vehicles. Almost any vehicle can outrun it after closing to just within its main gun's range to strike it and then fleeing. The tracks are designed make it possible for a tank to be used for off road deployments, but experience has shown that the tanks are rarely deployed off road in military engagements and that wheeled vehicles, like the Humvee which was designed to be able to go anywhere that a tank could off road, can be just as effective or better off road with greater fuel efficiency and speed when on the road. 

The high speed, high temperature jet blast emitted from the rear of M1 Abrams tanks makes it hazardous for infantry to take cover or follow behind the tank in urban combat.

And, because of their great size even if they are running in all electric mode for a short time removing the rumble of their engines, the crunching of their tracks and large slow moving bulk make them hard to miss.

The Marines did the right thing in dropping the conventional tank entirely from its arsenal in 2020, transferring its 450 Abrams tanks to the Army.

The Army would do well to follow suit and to not directly replace the Abrams tank, which was the epitome of what the mid-Cold War era thought it needed (although it was rarely used in combat) but which no longer makes sense in modern conventional warfare except in niche applications that can be met with upgraded existing heavy tanks.

The Army has already spoken with its feet by replacing many of its heavy tank units with Stryker battalions (a lighter, wheeled armored personnel carrier), and almost every major military force in the world (including Russia) has greatly reduced the number of main battle tanks it has in the last thirty years. 

A conventional Abrams style tank has too short a range for its main gun, and the concept of heavy armor is one that anti-tank missiles has largely made obsolete. A light or medium tank to use against mechanized infantry without heavy weapons may still make sense, but active defenses are the only viable defense against anti-tank weapons, heavy armor just slows down the system and makes it less nimble without ultimately being enough to prevent it from being destroyed by anything bigger than small arms.

The Gulf War in which the Abrams first so hot war action, which began in 1990, was the beginning of the end of the tank as core weapon of war, and the Ukraine War is shaping up as something close to the end of the end of that era, although not quite a decisively as the "charge of the light brigade" which ended the use of horse cavalry as a major instrument of war. In Ukraine, even Russia's heaviest and most modern tanks have fallen easily to Ukrainian anti-tank missiles.

The Abrams has never been really a decisive or pivotal factor in any of the wars it has been used in. 

For example, as a tank killer in the Gulf War, the Bradley M2, A-10 aircraft, attack helicopters, and other fixed wing aircraft were just as effective at destroying Iraqi tanks as the Abrams was.

It is hard to think of an instance where tanks were used "to rapidly punch through enemy lines while wielding large amounts of firepower to eliminate a host of obstacles, whether that be vehicles, infantry, or other tanks" in recent history. Certainly, this has not been a tactic employed by the U.S. military. And, if one imagines future conflicts it is hard to imagine one where it would be. Indeed, the concept of "enemy lines" is increasingly doubtful.

The U.S. is not going to invade mainland China with heavy tanks, nor is there any need for them in a foreseeable military conflict in North America. 

Even the mighty U.S. military doesn't have the ability to deploy a meaningful number of 64+ ton Abrams tanks to a foreign theater of battle where the U.S. does not already have military bases where they are prepositioned in a time frame that would matter in the rapidly developing military conflict, which largely rules out their use in large numbers outside Europe, South Korea, or perhaps Iraq or Syria. 

They might be useful elsewhere (e.g. in African conflicts), but by the time enough tanks to make a difference could be delivered, the phase of the conflict in which tanks would be desirable to "break though enemy lines" or some such would be over.

In most of the conceivable European conflicts where heavy tanks would be deployed, considerable anti-tank weaponry would be available to U.S. military opponents profoundly undermining their usefulness. And, our European and South Korean allies already have ample supplies of their own tanks. They would look to the U.S. mostly for air support, not for additional heavy tanks. Taiwan has purchased 108 Abrams tanks from the U.S. of which 2 have been delivered so far. They have also been sold to Iraq, Kuwait, Egypt, Morocco, Australia, and Poland. Brazil and Greece have contemplated purchasing them.