Armored personnel carrier (Tiberian Dawn)

Given their reliance on infantry (at least more than the Soviets), the United States was the creator of the original M113 APC, which they later supplied to the Allied countries in large numbers. The vehicle was relatively small, heavily armored and fast. Mounting a small machine gun (though later, an Armored Cavalry version with a .50 caliber machine gun was developed, but rarely seen), it was effective against infantry and it's speed and ability to crush infantry made it highly effective against soldiers of all types - with the exception of the shock trooper, whose electrical backpack prevented him from being crushed. However, the machine gun was still effective against these targets(it's turret does not turn). Although it could be used to transport engineers, the number of engineers required to capture most buildings meant that this was often not an effective tactic. The later Allied phase transport was built around an M113 chassis.

During the First Tiberium War, GDI used an updated version of the APC. it had some minor but important improvements (its gun was now in an actual turning turret). However, owing to the different nature of that conflict, the APC accordingly had a different role. Although powerful against infantry and able to crush all types, the ability of the Engineer to capture full strength buildings meant that the APC could be used to transport Engineers into fortified Nod bases and have him capture enemy buildings, putting them to good use for the GDI.

Armored personnel carriers could also be used as scouts, owing to their speed and their ability to absorb more damage than could the fragile Rangers or Humvees. One important feature that the APC provided was the ability for infantry to cross Tiberium fields without damage. Nod also fielded the M113, as it was relatively easy to acquire. However, Nod was finding it difficult to acquire in the numbers required, and deciding not to reverse engineer it, Nod instead opted to field their own APC, which would essentially serve the same functions the GDI M113 did.

In the post-war world, APCs became more important than ever as the Nod factions turned in on themselves, and the increasing Tiberium proliferation required safe transport. Both APCs would commonly be seen leading assaults on enemy positions. While a reunited Nod fielded its own new Subterranean APC, the old APCs could be seen as late as past the Third Tiberium War in service, with militants, civilians, or otherwise.

Behind the scenes
In reality it is made in the USA. In Red Alert its whole body must face the enemy infantry to attack but in Tiberium Dawn it can turn its gun.