I recently had to remind a friend that Libertarians aren't against all government.  The founding fathers acknowledged that government is necessary.  However, they made specific limitations on how large and intrusive that government should be.

1)  "Provide for the common defense."   We need to protect our nation with a strong military.  It is not wrong to expect the citizens to pay for this.

2)  "Insure domestic Tranquility" and "promote the general Welfare." do not say it all.  We need government rules that discourage citizens from harming others, however, this can easily be misconstrued to mean that no citizen should ever suffer discomfort, etc. 

To provide all a citizen's needs is socialism and this has been proven a failure.  If you mandate provisions for one citizen you must take them from another.  Who wants to be the provider and who wants to be the receiver?  You discourage ambition when a worker knows what he/she earns can be taken away. 

Most workers are willing to share some of their profit, however, even the altrusitc Christian ethic says, "If anyone does not want to work, neither let him eat." (2 Thessalonians 3:10)  To give too freely is to ENABLE laziness.  The US has become the "Great Enabler".

3)  "Secure the blessings of Liberty" shows that the Founding Fathers recognized that freedom was a blessing.  It was for this reason they took steps to limit interfence by citizens and government.