The early European-American settlers still had a basic expectation of the availability of natural resources. In the case of Mars, natural resources aren't simpl

The early European-American settlers still had a basic expectation of the availability of natural resources. In the case of Mars, natural resources aren't simply an unknown, we know Mars to be a desolate place largely free of any valuable resources. This knowledge may change with boots on the ground, but the risk to those explorers far, far exceeds the risk taken by those early colinists.