Why did pioneers often regard the environment as an adversary?

The new lands in the western US were usually mountainous and the environmental circumstances hard to survive, so that early immigrants often appeared to be conflicting with nature as an adversary or opponent.

There were no structured lodgings in the newly settled lands. The pioneers and immigrants suffered severe weather conditions such as storms, floods, hurricanes, dust storms, and utmost heat and cold.

The tracks they used required to be cleaned of rocks and trees, and cross mountains. These calamities tested the capabilities of the frontiersmen and pioneers, who regarded the environment as an adversary.