Some people fear the idea of a world government, just as the newly independant American colonists did at first. History tends to ignore the first 7 American Presidents: John Hanson, Elias Boudinot, Thomas Mifflin, Richard Henry Lee, Nathan Gorman, Arthur St. Clair, and Cyrus Griffin, who each served their prescribed 1-year terms between 1781 and 1788. Like the League of Nations and the United Nations, The Articles of Confederation proved to be too loose a union to be fully effective. (Still, we should remember the real first Presidents. The one-year term might have been a better idea than four, actually.)

Many great thinkers besides me have advocated working toward a united world government
Consider the resources and lives that are needlessly wasted in simply protecting resources from others with whom we refuse to share.
Consider the millions of people who have died needlessly because they were forced or manipulated by governments, religious leaders, and powerful corporations into fighting wars.
The divisions and our habit of thinking of ourselves as different and better than others elsewhere are what make wars possible, and easy to start.

People everywhere are easily manipulated by the power-seekers and wealth-seekers because most people do not have a vision of how things should be; they don't have a sense of unity with everyone on the planet, so they are vulnerable to propoganda that exploits their fears.

Lets hear from a few other well-known people on the subject:
As long as there are sovereign nations possessing great power, war is inevitable. There is no salvation for civilization, or even the human race, other than the creation of a world government.
--Albert Einstein

It will be just as easy for nations to get along in a republic of the world as it is for you to get along in the republic of the United States. Now when Kansas and Colorado have a quarrel over the water in the Arkansas river they don't call out the national guard in each state and go to war over it. They bring suit in the Supreme Court of the United States and abide by the decision. There isn't a reason in the world why we can't do that internationally.
--Harry S. Truman

We must create world-wide law and law enforcement as we outlaw world-wide war and weapons.
--John F. Kennedy

There are many others. Check these quotes
One of the many serious offences of the Bush Administration was not just invading Iraq, but going against the decision of the United Nations in doing so. This weakened the unity and influence of the UN and of the concept of international law.
Though the UN is an extremely valuable organization, it cannot insure peace without having authority over the governments of its member nations. It is similar to the first American government. It needs a new constitution, with a legislative body elected directly by the people of the world.

Those who think that world peace is just a left-wing liberal idea should read what President Dwight D. Eisenhower said:
Every gun that is made, every warship launched, every rocket fired signifies, in the final sense, a theft from those who hunger and are not fed, those who are cold and not clothed. The world in arms is not spending money alone. It is spending the sweat of laborers, the genius of its scientists, the hopes of its children....This is not a way of life at all, in any true sense. Under the cloud of threatening war, it is humanity hanging from an iron cross.

As the former Supreme Commander of Allied forces in WW2, Eisenhower knew what he was talking about. They don't make Republicans like him anymore.

It is the people, not the politicians, who will make a world government possible. We must think it; dream it; demand it. The American people finally stopped the war in Vietnam, and now we need to stop the one in Iraq. But too many die, and too much is wasted between the time the politicians start a war and the time the people can stop it.
As Benjamin Franklin might have said:
A gram of prevention is worth a kilogram of cure.

--Captain Rat Sept. 2005.