How were the american indians largely responsible for the success of european settlements?

American Indians are responsible for the success of European settlements due to many factors such as trading ; furs,maze,potatoes,tobacco. In political terms the Indians made alliances between warring European nations aiding one over the other (British vs France). In the Spanish settlements the Spanish befitted from the silver mines which use Indian labor. (In Europe the Spanish suffered inflation due the silver influx).

There are many other reasons why European settlements where successful.
In my opinion the American Indians helped the Europeans by simply dying due to the lack of exposure to disease (exposure to diseases increases resistance).
This period can be neatly summarized in the documentary:
Guns,Germs,and Steel