The six precepts, 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, are goals defined in the constitution. Basically, things that the states themselves could not do by themselves.
A common justice system, resolve conflicts between the states, maintain a military and protect our borders, promote intrastate commerce, defend individual rights as outlined in the constitution, and coin money.
The problem has been that the federal government has expanded its role and power far beyond what the founding fathers had envisioned.