"... the chief business of the American people is business." he once said.
Coolidge followed a laissez-faire economic policy, whereby the government doesn't interfere in the national economy unless absolutely necessary, and even then its actions should be limited to gentle nudges to get the economy back on track rather than large scale intervention.
So, Coolidge's attitude toward business was 'if it's not broken, don't fix it' - leave business alone to prosper.
It was a United States foreign policy document. It stated that if European nations tried to colonize land or interfere with states in north or South America it would be seen as acts of aggression which then required us intervention
Westward expansion was a natural progression for the nation because the most powerful entities came from the East (England). It is only natural that they spread out and conquer/capture/kill/annihilate those in their way (the true Americans/Native Americans). In doing so they conquered a whole land and taught them their ways while spreading West.