In modern warfare (and it has actually been this way since about WWII), you have to make sure that enemy air power doesn’t hinder your ground forces too much. You can have your own planes try and neutralize them, but your aircraft can’t be everywhere at once. As such, having anti-aircraft elements in your forces is imperative. That can take the form of Surface-to-Air Missile launchers. And that’s just what we’ve got here for Team Yankee.
From the article:
The SA-9 Gaskin (its NATO designation), called Strela-1M (Arrow 1M) by the Soviets, is a wheeled, amphibious Surface-to-Air Missile (SAM) system based on the same vehicle as the BRDM-2 reconnaissance vehicle. The missile system has both optical and infra-red guidance, and a target ranging radar.
Each vehicle carries four missiles in a ready-to-fire configuration and the crew would then manually load additional missiles once fired. Designed to protect against short-range threats it would often be deployed in conjunction with batteries of ZSU-23-4 self-propelled gun systems making a deadly combination.