This is a modern medal issued by the American Legion in commemoration of the heroes of the Vietnam War. It has a Legion seal on one side and a picture of the National Vietnam War Memorial, aka 'the Wall' on the other.
These are modern pieces made of non-precious metal. Typical sales to collectors register as follows:
circulated: $2 US dollar approximate catalog value
fully uncirculated: $8
If you wanted to sell one of these medals to a coin dealer, he or she might pay $1 or so for it.