The purpose of government is to make people better than they otherwise would be.
An ideal government has the consent of the governed. IE, the people realize their own flawed nature, their own weaknesses, and ask for the government's help to POLICE THEMSELVES towards their better angels instead of their demonic, animalistic impulses. This is because they know they will have a better life if the good is brought out of them, and their neighbors, instead of relying on their natural, and their neighbor's natural, states. This is also because parents realize they need all the help they can get to raise their children to be good people, and if society is hell-bent on corrupting them, there is nothing parents can do to save that which they love most on this Earth.
The government's role can be performed in many ways. Law is one of them, but it isn't the only one. Taxation and spending policies are another tool in the arsenal of human betterment. Lastly, there's education and 'culture.' When the government recognizes official holidays and celebrates them lavishly itself, while subsidizing their celebration among the people, that's 'culture' at work. The government is the most powerful force in the universe, it has enslaved electricity since the 1800's and surpassed gravity in the 1960's, and it can be the greatest force for good in the universe, using these 5 tools, if it so chooses. Nothing else can compare. The unified strength of a group of people will always surpass any particular individual, and the unity of government will always be stronger than any other unifying bond. ((For instance, even though there are 1.2 billion muslims on Earth, they never act in concert, so it's easy to bomb first Afghanistan, then Iraq, then Libya, without any unified response, but only local governmental-national responses each time.))
People who wish to unilaterally disarm, ie, have some sort of minimal government that only uses one of these five tools -- law -- will obviously fall behind those who use all five to their maximum potential to improve mankind.
People who wish to get rid of even law will quickly find that without government people are naturally evil and only destruction awaits them.
The fact that people are naturally evil without government does not mean that human nature is evil. Human nature evolved with government in mind. Government is part of human nature and it has always been with us, it is a tool as essential as our brain, body, clothing, hunting spears or computer terminals. Human nature, when government is taken into account and used, is actually quite peaceful and productive. Even though it takes twenty years to raise a child, it only takes a few seconds to snuff out said child's life. Even so, most people live to old age and very few are killed. The difference is astounding. That something so hard should be more probable than something so easy denotes a wonderful human capacity for good. But that capacity relies on government and cannot last without it.
Those who use fewer laws to improve mankind will naturally fall behind those who rely on more. The more totalitarian your state, the better. Because government's sole purpose is to improve mankind, there can never be too much of it. That's like saying humans have some fixed amount of good they can be and being any better would be counterproductive.
There is no such thing as too much government. There is only 'ineffective' government. When a government, by being forceful and aggressive, demands people act in certain manners, but the results are the exact opposite of their intentions, the problem wasn't the goal -- 'a better populace,' or the means -- 'forceful, aggressive policymaking,' but solely the methods -- 'collective farming' or 'gulags.' When 'big government' fails in its mission that does not mean we should give up government, our better angel's best and strongest ally, in principle, but solely those methods that failed to produce the results we wanted and expected.
A scientific culture would keep tinkering with the five tools government has at hand -- culture, education, taxation, spending, and law -- to produce maximum results. We would copy things that work from abroad and wouldn't cling to any particular formula, always looking for innovative ways to improve our populace. If a policy didn't work, like throwing dissenters into gulags, we would quickly abandon it and try something else. ((The soviets quickly discovered simply denying dissenters entry into college was punishment enough to win full obedience.)) We would create a laboratory of independent states and they would all compete with each other under a dizzying variety of plans, where we could just see for ourselves which policies worked best on whom, where, how and why.
The excesses of 'big government' have always been their methodology, not their nature. Since government is designed scientifically, by a collection of the brightest minds in the nation, it will never fall short of any individuals' thinking. IE, leaving each individual to 'better himself' is absurd, as most are too stupid and all are too few to match the collective intelligence of a governmental hive mind dedicated to 'bettering everyone.' Furthermore, the government has tools the individual lacks in 'betterment.' An individual can't pass laws, but a government can. An individual can't create a new culture, only the government can. An individual can't embark on a trillion dollar spending program, but for the government that's pocket change. And so on. Even if individuals could somehow conceive of ways to improve themselves better than the concerted efforts of the brightest minds in the world could, it would be pointless because only governments can actually put into play any such efforts/reforms.
Government is more powerful than human nature. Note, for instance, that nothing has genetically changed between the Vikings of old and the Swedes of today. But Sweden has become a completely different nation. This is because Swedes today have different educations, a different culture, a different law code, and different taxation and spending policies than they did as plundering Norsemen on dragon ships. Not only that, but its quite apparent that modern Swedes live longer, healthier, happier lives than their ancestors, and they also cause the rest of Europe a lot less trouble. Everyone wins. Human nature is just one more obstacle to design around, like the law of thermodynamics. No governmental policy should contradict human nature, that's like imagining away the law of gravity, but there's always a way to manipulate it. Whenever scientists discover a natural law, they do not then throw up their hands and say 'humanity is powerless, we may as well live in straw huts and give up.' They say, 'how can we use this to empower ourselves? how can we trick the universe's natural laws into serving us and our desires instead?' They think about it, and then they come up with the internal combustion engine. Or the transistor. Or whatever. And life improves.
Government must do the same about human nature. We must enslave the drives and natural impulses of man, just like we learned to enslave electricity, wind, water, and every other force found in nature. Take whatever is out there and build canals that route it to serve human needs. Nature is all-powerful, but it's also powerless, because it can't assert itself. The same for an individual's instincts, which stand no chance against the will of the people, backed up by trillions of dollars and millions of heavily armed soldiers. Sure, it is impossible to stamp them out, but it is possible to sublimate them into any number of alternative pathways. The mating instinct can be turned into a courtship plus marriage culture. Selfishness can be courted into the 'invisible hand' of economics. And so on. There is no human instinct that cannot be turned, even 180 degrees, into a force for good. Careful scientific planners have found ways to harness the lightning and the heat under the Earth that drives volcanoes to serve human needs. Compared to that, what chance do a few human instincts have?
If people do not realize it is in their enlightened self-interest to consent to a government that is designed around improving themselves and their neighbors, then it is still permissible to rule them. This is because they are too stupid and evil to rule themselves, and will just make a mess of their own lives, and the lives of those around them, and the corner of the environment/natural resources upon which they sit. No one has a right to waste space or breathe air. That could always go to someone else, someone more worthy. This principle is best described by: The superior should supplant the inferior, but the inferior should not supplant the superior. We don't have time or space to give a continent away to stone age barbarians still using human sacrifice and cannibalism to get by. We must conquer those places and put them under the law, the government, and quickly improve them to a point of minimum acceptability, so that the Earth's utility is maximized.
Part of forcing people to accede to governments they do not consent to is quickly teaching them to consent to them. Part of our duty, when we make unwilling servants out of unassimilated groups, is to assimilate them. Use the five governmental tools to quickly beat them into shape, until they, or at least their children, come to realize the benevolence and grace of the government they exist under. If a group stubbornly refuses to acknowledge the benefits of their government, and refuses, generation after generation, to assimilate to it, the only choice is to deport them or kill them off. Killing them off can be done in a variety of ways, by limiting their childbirth rates to 1 per family, etc. It needn't involve any pain or distress to the living. But in any event we cannot allow rivals to the government to form. People who have their own governments, or people who systematically disobey the government, or people who constantly proselytize to the masses against the government, will topple the world's greatest force for good given time. They are like a cancer and they must be cut out.