Govern

The first thing the government does is govern, making laws to regulate interactions between people, organizations and states. The government is the only body with the authority - given by each state when they ratified the constitution or came into the union - to make such decisions. The purpose of the US government as stated in the Preamble to the Constitution is to:

establish justice, insure domestic tranquility, provide for the common defense, promote the general welfare, and secure the blessings of liberty to ourselves and our posterity.

In other words, the federal government is supposed to bring everyone three well-defined conditions: (1) justice or fair treatment under laws, (2) peace within the nation, (3) defense against foreign threats, and two more-encompassing and less-defined conditions: (4) improve the general welfare, and (5) bring the blessings of liberty to our people, now and in the future.

Individual people and corporations can not make decisions about these conditions because they have no mandated authority nor accepted ability to enforce their decisions. In the US government the laws are made by elected representatives of the entire population. When control of a nation is by an individual or unelected group that is a dictatorship. Our government seeks to preserve liberty by limiting the power of even elected officials .