When I used to hear, “WWI tanks,” I would think of the British rhomboid-shaped tanks. They were, to my way of thinking, fairly task specific. After the outbreak of hostilities, in short order both sides had dug into trenches that stretched for ridiculous distances. Between the two trench lines was “no man’s land,” an area of shell holes, barbed wire, and little cover. People would go over the side (up the trench walls and onto no man’s land) and charge the other trenches. Barbed wire restricted access, forcing attacking forces into choke points where machine guns would pile bodies high. When the attackers had enough, they’d make for their own lines. Less came back than went out…and this went on for years.
The Brits came up with a solution. They developed a mobile armored strong point that could lead attacking troops across no man’s land, offer some cover during the crossing, and then straddle the trenches and open fire. If you look at the placement of the armaments on the British tanks, that explains their placement:
British Mk I
They were large and since they were intended to support infantry, they didn’t move faster than a walking pace. They were also complicated for the time and as new technology frequently is, they were also mechanically unreliable. The Brits’ code name for the new project was “tank,” implying that it was a water storage device.
The French had a different idea (what a surprise). Designed in 1917 and the project overseen by Louis Renault, their machine was much smaller and from what I can tell, much more mechanically reliable. What was also interesting about the FT-17 is that it seems to have become the first tank with the layout that has come to be almost universally adopted (Israeli armor excepted). The engine was in the back, the crew (driver and commander/loader/gunner; there were only two) in the front, and the armament in a fully traversing turret. The armament during WWI was either a Hotchkiss machine gun or a small 37mm cannon.
As you can see, it wasn’t a very large machine.
During WWI, the US Army was ill prepared or equipped for the European war. As with the aircraft the American Expeditionary Forces used, its armor was also equipped from external sources. The US built a licensed version of Renault’s tank, being slightly larger and a little modified version of the FT-17 and named it the M1917. As far as I can ascertain, no M1917s saw combat. The AEF used the FT-17 with the riveted turret and was armed with the 37mm cannon.
During the 1920s, M1917s were deployed with the Marines in China and, oddly enough, some FT-17s were used by the French in the opening months of WWII, even though obsolete. The Germans used captured FT-17s for basic sentry duties and the cast version of the FT-17 turrets were also used on fixed fortifications.