The Role of the United Nations Today.
The UN is an organization that has many roles, one of which is to keep the world at peace. The UN will never start any conflicts, as it is only there to try and resolve them. This organization could be considered the police of the world. During wartime the UN considers themselves "peacekeepers," a term that came about during the 1956 Arab-Israeli War. The term has been used extensively since then to describe UN-sponsored military operations designed to control conflict.
United Nations peacekeeping operations go in and try to contain or halt conflicts long enough to allow opposing sides to enter negotiations towards an effort at lasting peace. In doing this the UN has taken over a number of roles, they have observed border violations, monitored cease-fire and truce lines, served as a buffer between opposing sides, and maintained order within a territory during transition periods. The United Nations is an organization that will never start conflict, it is only there to try and resolve it. .
Though the UN is supposed to try and keep the world at peace things don't always work out that way. Some countries will go against the UN's decisions and still choose to take over other countries or start conflicts. In some situations they are able to stop the rebelling county, but not always. If the UN needs to send in some troops to "peace keeps," it doesn't have its own troops to send in. If troops are needed they must be volunteered from a participating country. Yet if the countries don't whole-heartedly believe in the cause, then why would they risk their men for it?.
Even if the security part of the UN is not perfect that is not the only thing that the United Nations has done for the world. One large organization developed form the UN is the World Health Organization. One of the WHO's objectives is to try and stop the spread of diseases through vaccinations.