OE would respond....
You seem to be assuming that governments either should or must exist for civilization, law, and order to exist, an assumption with I disagree with. However, I will not challenge that basic assumption here. Assuming that governments will exist, the question then becomes what type of government. That is, should we have one government for the entire world, or many governments as is the case now? I think the best solution possible is the exact opposite of the one world government you described.
A better solution would be an extremely large number of extremely small sovereign states. In this system no one state would be able to limit the rights and freedoms of its citizens very much. Any time some state attempted to impose some unpopular ordinance or law, people would simply vote with their feet and move to nearby nation states which are more suited to their tastes.
Most people will move hundreds of miles for a good job or college or to be with family. The system I’m describing is better for the individual because most people would not mind moving to a different sovereign county or city that better suited their political tastes. Consider the state of Virginia. Some liberal individual living in rural Virginia need only move a relatively short distance to Washington D.C. where they may enjoy higher taxes, gun control and the generally leftist government we see in that city. Some conservative living in Washington D.C. need move only a relatively short distance to find a state which offers lower taxes, no gun control and a more conservative form of government. It’s a win-win regardless of your political persuasion. What is important to grasp is that any individual need move only a short distance in order to live under the kind of government that he or she desires. The current state of affairs is difficult enough. If a person is tired of America and wishes to live in another country he must get used to another culture. But in the many-mini-state system an individual need not move to another continent and begin the difficult process of getting used to a foreign culture, though he still would be free to do this if he really desired it. Instead he will probably need to move only a relatively short distance, something people are already doing for careers, education and other reasons. But if there were a one world government there would be no incentive to move. An oppression anywhere would exist everywhere and people could not vote with their feet. There would be no escape from an oppressive government.
You never stated it outright but you seem to be assuming that this one world government would be a peaceful democratic one which ensures freedom and personal liberty. However, why should this be the case? Why should a government which has no competitors care about its citizens? If some grocery chain, lets say Wal Mart, had a global monopoly on the sale of groceries, what do you think would happen to the price of groceries? And what about quality and customer service?
People who do not like their country are free to leave except in extreme and unusual circumstances. But in the global monopoly you describe, it would be impossible to leave. Going back to my example of Wal Mart having a global monopoly I doubt anyone would say that an individual is bad or evil for wanting to shop at some other grocery store besides Wal Mart. What would be the best solution to this problem of the global Wal Mart monopoly? The best way to get Wal Mart to increase their service and decrease their prices would be through competition. Suppose that only one competitor came into the market. What would happen then? This scenario is better than the Wal Mart only scenario but is still far from ideal. Now let’s add another company into the market so that there are only three grocery store chains worldwide. This is clearly better than the Wal Mart only scenario but things could still improve. Keep adding companies into the market one at a time and what would you find happening? As competition increases prices go down, quality goes up. It’s economics 101. If a very large number of competitors sprang up in the Wal Mart only scenario this would be great for the consumers though bad for the owners of Wal Mart.
But all this is directly analogous to the one world government scenario you mentioned. A one world government has no incentive, no competition which insures that prices stay low while quality stays high. With governments price is paid directly through taxes or indirectly in inflation of a fiat money system. Quality may be measured in personal freedom and liberty as well as services such as police and the criminal justice system.
What has happened in your lifetime? Has the price of government gone up or down? What about the quality of services the government provides? Have our liberties increased or decreased in your lifetime? Would you say the criminal justice system has gotten better or worse? Don’t you think it’s about time to introduce some competition into the marketplace?