The current push to replace the formidable heavy tank has two very important reason why it may be real. First, the modern tanks have gotten so heavy that they have limited their mobility. This is most particularly the case with bridges. In many parts of the world, there are lots of rovers to be gotten across, and few bridges can handle 60-70 ton tanks. Nothing new here, even during World War II there were many bridges that could not take the 20-30 ton tanks common then. The solution has always been to have special engineer units available to put up temporary bridges as needed. But the equipment needed to erect bridges for 70 tons is itself heavy, and expensive. The result, M-1 tanks won't be able to get across rivers as quickly as lighter armored vehicles. This is a real problem right now, for the only place where tanks have been used on a large scale in the past few decades have been desert areas. The bridging problem has been sort of pushed into the background, as it doesn't show up in desert campaigns. But there is another problem as well. A new type of weapon is about to be put into service. These are the very high speed projectiles, of which the U.S. LOSAT rocket is the best example. In addition, there are the older, but still effective, anti-tank threats like top attack ATGMs (which can take out the M-1) and land mines (which, at the very least, slow you down.) Had Iraq possessed top attack ATGMs or LOSAT, there would have been higher M-1 losses (although still a coalition victory.) The new anti-tank weapons are becoming more widely available. A foe armed with these, and operating in a region requiring heavy bridging units for the M-1s would show the other extreme of tank warfare with vehicles like the M-1.
The US Marine Corps has set up an office to design its own new tank to enter service about 2020. This annoys the US Army, which has previously provided the Marines with their tanks and artillery. The Marines are determined to seek a radically new vehicle, one based on technologies that do not even exist in 1999. The weapon is to be a laser or rail gun, as the Marines do not want to have to haul truckloads of large-caliber tank rounds to the front lines. The armor must survive a 105mm cannon shell hit, but must weigh half of modern steel-laminate armor. This will require inventing new composite materials. The Marines also want a tank that doesn't burn hydrocarbon fuel, and which has an integrated battlefield intelligence system to maintain the best information on where the enemy is located. The tank is to include advanced defensive systems, including those which can automatically detect an incoming attack and deploy some kind of countermeasure to stop it. The Marine plan is to review new technology until 2004, then spend a decade developing the most promising new concepts. A development program would then start to design two competing vehicles, one of which would enter production and service by 2020.--Stephen V Cole