What is the Purpose of Government?

The other day a libertarian-leaning friend told me that he believed that the purpose of government was to protect us from each other, to protect us from foreign countries and to promote commerce.  I agree that these are all legitimate functions of government, but I think they fall short. 

For me, the purpose and legitimate function of government is set out in the Preamble to the Constitution which states:

We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.

In the Federalist Papers, James Madison argued that the Constitution gave the government the power do whatever was necessary to carry out the purposes set out in the Preamble.  Both Madison and Hamilton were proponents of a muscular federal government.  

The Constitution goes on to enumerate specific powers, such as to coin money, to regulate interstate commerce and so on.  However, I think that those enumerations do not limit the broader purposes set forth in the Preamble.

I would go even further.   Before the Constitution, there was the Declaration of Independence.   The Declaration set out founding principles of this nation. In its Preamble, Thomas Jefferson wrote:

We hold these truths to be self-evident,  that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty, and the Pursuit of Happiness.   That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed.  

Here we go to the very justification for government.  Government exists to to ensure that all men are created equal and to secure the unalienable rights of Life, Liberty and the Pursuit of Happiness.   

W

When we take these two founding documents together, it is clear that the purposes of government include protecting us from each other and protecting us from foreign governments.   However, it also includes protecting the equality of citizens, perfecting the union that binds us together and promoting the general welfare.   There is also a strong commitment to justice and liberty.    

Often these purposes may compete against each other.   For example, requiring people to contribute to social security promotes the general welfare while taking away the liberty not to save for retirement.   Enacting regulations against dumping coal waste into rivers promotes domestic tranquility and the general welfare while protecting the right to life while it limits the liberty to pollute the environment.   While there will always be trade-offs, I think that government is acting properly when it promotes one of these core values without substantially limiting or destroying another core principle.