World Unified Democratic Government
Disclaimer: If you do not understand that this is only a theory and perspective I came up with based off of history, government, failing foreign relations and aid and will cover a lot of controversial territory. However, I do appreciate ideas and criticisms, just keep your replies civil in tone. This is just a possible perspective, I am not being literal in my own beliefs and opinions.
Touching on the failing foreign relations and aid, I'm going to reference war-torn nations like Darfur, Ethiopia and pretty much the entire Middle East. These nations have been entrenched in civil wars resulting in genocide, ethnic cleansing, killing in the name of a religion, and many other factors. These nations have been warring for decades if not centuries. The original reasons for some of the fighting is long forgotten, other times it's because a group of militants is wanting to seize power any way he/she can. The foreign aid we send to these kinds of countries often does not go to the people who truly need the help, ends up helping the wrong people, or just disappears. Why try to help nations like these that can't or won't willingly accept help from other nations? Even if it is the responsibility of the strong to protect the weak, if our efforts are futile why should we waste our precious resources in that futility? I say we just let them kill each other off and see who the victor is. After wars like that are done, only then can we sweep in and help out. People that believe talking and negotiations is the only way to true, lasting peace are naive. While that is my preferred method to reach peace, some nations won't bow down to that and need a push with a threat of all out war.
By taking the methods of how the Roman Empire (pre-Christianity) conquered a chunk of the known world at its time, we could create a largely peaceful world government. We, being the strongest nation, have the power, allies, and governmental structure to do so. The countries we conquer would lose nothing of their ethnic, religious, and regional uniqueness. We would simply move in, cultures would assimilate on both sides and a common language set. If a country did not want to peacefully join, one would hope just the threat of war would throw them into peace negotiations. This would bolster both the ruling government and the nation's trade and economic infrastructure. It would be win/win for both.
The democratic structure of the United States is pure genius when you analyze how it's broken down. It could truly work on a worldwide scale. Each nation would in essence be like what states are now with laws, elections, and governmental structure. There would be a vast senate in what would be he federal/national arm of the government so there would be equal representation for each nation. There would be no more United Nations because how they work well, they don't. The Electoral College would be wiped from the board for elections and a new, better system would be put in place to accommodate such a large voting body. The separation of powers between branches of government would remain intact and so would the checks and balances, but with improvements again to accommodate such a vast body.
This isn't a grand scheme for the U.S.'s world domination through war. There can be no truly lasting peace with a nation unified through fighting. There has to be reason and peaceful methods tried first before force is used. If those peaceful methods are futile, war is the only way. You can't repeatedly sanction a nation into peace or do the equivalent of shaking a stick at it to bring peace. Action would be the only effective answer.
I am not proposing a utopia. I firmly believe that it is impossible for humans to live in a true utopia. I am proposing a unifying governmental structure to bring about a lasting peace between nations that will bolster international trade and economies. If a state (calling them that for this system) has the resources to build infrastructure and have the things it needs, there is no reason for it to fight against or commit violent acts against other states. Especially those nations providing it with those resources. There would be no "foreign" dependencies because each state would be a part of the name nation and sharing resources.
The United States hasn't had a civil war in well over a hundred years. This, I believe, can largely come from the fact that we moved from an agriculture-based society to an industry-based society. We beat out the dissidents who thought to break the country apart through force as it was the only way.
One of the biggest flaws in a system like this is unavoidable in any political system and to complain about it is completely and utterly unintelligent. The issue of leaders. I believe that having a singular leader for a system like this would be a downfall and would create the downfall of it very quickly. The biggest reason Rome fell was because a single, crazy, warmongering leader was put in place. Had that not happened, we just might all be speaking Latin and not English.
The Executive Branch would consist of not just the cabinet of the group of leaders, but an odd numbered group of people. A sort of council but not a legislative body.
The Judicial Branch would be nearly the same as the Judicial Branch of the U.S.
The Legislative Branch would work the same our the U.S.'s as well.
This kind of setup would trickle down to states as well. We would see essentially the same setup we already have now but on a global scale.
Right now I don't think this could work. The world nor the politicians of the world are not ready for this. They are too centered on themselves and their own personal welfare rather than thinking about unity on a global scale. Peace on this scale is not attainable with the current state of affairs and I'm guessing probably won't be in the next 50-60 years. Though when the world is ready for it, this would be an effective way to go about it or at least a decent model.