Radioman purpose?

If you are playing as America, what does a radioman do that the static radio on the map doesn't already do? Vietnamese commanders can act as an emergency spawn point if a radioman is near. I don't think that's the case for America. As far as I can tell, American commanders have very little incentive to be close to the fight and therefore want a radioman. It's seems like a boring role that requires a lot of work that has very little payoff and even scores poorly when you do it well.

Someone please tell me how I am wrong.

Radioman purpose?