Why do not Mercedes sell their trucks in the USA?

Mercedes make a big range of trucks, in fact they're one of the worlds biggest marques. But why do not they sell them in the USA? Sprinter Vans are Mercedes during the world, but they're Dodge/Freightliner in the US, the Unimog is a Unimog in the States, but Mercedes else where? it looks weird.

Mercedes wanted to be seen as a premium car line in the US and felt that having trucks with their name on them could hurt that image. They have sold their heavy responsibility trucks here in the past but not the light and mid responsibility trucks.That is why they only send the top trim level cars to the US.