Scenario: Anti-UN Alliance

Sure, the term "United Nations" sounds powerful and implies the unity of the nations of the Earth. However, all is not as well as it may seem. Few nations can relax while Taiwan is on the Security Council's list of permanent members while the several-hundred-times-larger China is not; France, another member on the security council, has lost the last several wars it has fought (World War Two, Vietnam, Algeria); America and Russia remain diametrically opposed. Soon, in a few decades, the predominant global situation will change.

The Years of Waiting
The world is not yet ready for the birth of the in-effect "Anti-UN Alliance". For that to happen, several decades must pass, during which the developing nations can partially catch up and during which the developed nations will run into trouble (Russia's 80+ minorities' seeking independence; the Kurds; the Basques; minorities in China and India; Israel vs. Muslim Brotherhood, etc) resulting in a weaking of their power. This process may take several decades and will occur slowly as the recent trends may show.

The Birthing
The "Anti-UN Alliance" will not be called such, of course. It will be known as a protective league outside the jurisdiction of the UN, a coalition of minor, less-developed nations disillusioned with the UN, who pool their military under the leadership of generals holding allegiance to the league as a whole rather than to any individual state inside it. The league will be characterized by the following:

Traits

 * 1) Member states are generally poor and weak, developing nations.
 * 2) Military is pooled (rather than separately owned in the UN). It will be used for defensive purposes only, and not serve under any particular member state.
 * 3) The league grows rather quickly, combining the assets of over a hundred nations (from Eastern Europe, Africa, South America, Middle East, and Russia (splinter republics)).
 * 4) Each state has a say depending on its population and assets, as opposed to seniority and victory in war as the UN Security Council is.
 * 5) The league serves as an opposition to the NATO and Russian dominated UN

A Path to the Future
This league will serve as a vessel for another type of government to be introduced in the future: Global Parliament.