In conception, our system grants to States the ability to regulate morality. This point is crucial: to my mind, and I differ here from most Libertarians, liberty is both the right to be free from unnecessary burdens, but also to impose them, if they are generally desired. As an example, I wear a seatbelt, but respect the right of those who refuse to. At the same time, I grant that the State has the right to make that law. If people do not like that law they need to elect people who will repeal it. They have that right.
Political progress is in my view cultural progress, which is to say the capacity of all individuals within a social order to respect the rights of those around them, and to make few if any impositions on them. Given a sufficiently intelligent, reasonable, organized, goal-focused population, no government would be needed. If a road needs to get built, somebody takes the lead, figures out how to pay for it, and gets it done.
In the present world, however, many people need to be told what to do. We need speed limits, in my view. People need to be told not to drink and drive. We need to have laws against, and penalties for, things like theft, contract violation, fraud, murder, rape, child abuse, etc. Given a perfectly reasonable population these laws could just fall away. There would be no need for police.
But to my mind most Libertarians want to live in a world which we do not live in. There are many animals out there who will abuse people, given the chance. Absent a government, the law of the jungle would prevail, and that law tends to favor the most vicious, not the most reasonable.
Few thoughts. This is not quite as coherent as I would have liked, but it’s a start.