The film i mentioned above gives you an illustration that is pretty accurate on the happenings of the
Rwandan crisis, peaked in 1994. This is a conflict where approximately 1 million people died victimised bay atrocities and ethnic profiling that happened there. The civil slaughter between Hutu and Tutsi clans are amongst the most gruesome conflicts the world has ever seen, to date.
In that movie also you'd notice a bunch of military looking troops that attempts to assist people there, but you also notice that they're not really waging war. You'd notice that they do have guns and standard military equipments, but you also notice that seeing their behaviour, they're not so far from the other opressed casualties that flee into this Hotel. Ladies and gentlemen, i'd like to introduce them; these are the men in blue helmets..
United Nations have authority to pool up military resources from member states, although their participation remains voluntary (meaning a state can choose to or not to contribute military powers). Upon having the ability to pool up these resources, it does not then imply that UN have their own army, as there is no such no concept.
Peacekeeping operations (the usual term fro the deployment of the troops) can consist of military personnel, but can also contain civillian and journalists. A clear indicator of UN Peacekeeping troops is the contrast helmets in blue that they sport; hence the nick name of the troops are blue helmets.
Now, since it is tied to UN, as a nature of most UN operations, it does pose massive problems. If you read Linda Pollman's book, We Did Nothing, you can see her testifying how the troops in the Kosovo crisis never really managed to do anything, and ended up becoming witness of the atrocity that Slobodan Milosevic did, which resulted in 5,000 ethnic Albanians dead.
Most of the problems imposed within these troops are the nature that they are peacekeepers. They are mostly soldiers but they are not authorized to wage a full scale war and use agression to settle and extinguish the flames of a conflict. Their goal is among them are; monitor the withdrawal of combatants, supervise elections, and provision of reconstruction aid. They are not here to make peace or creat peace, but to provide aid. That means they cannot unleash fire at will, their weapons exist but only usable for means of self defence.
Another problem is support from states of the world. To pool in resources and convince states to contribute military personnell to be under the UN authority takes time, and while that time of negotiation and advocating to countries happen, people die by the day in the conflict zone. It took many moons for the UN to pool in the military power they needed in the Rwandan crisis, and as a result of the prolonging conflict, 800.000 - 1.000.000 lost their lives, children lost their parents, and families were torn apart.
Don't get them wrong, it's not like the UN does not realize the flaws of their peacekeeping operations. The Brahimi report was issued in the year 2000 to evaluate the humanitarian operations the UN have been conducting over several conflicts of the world. It does impose remedies for the UN to rectify the situation, and there is pressure for the UN to start implementing the mechanisms proposed in the Brahimi report in future operations, circa 2010.
Conflicts is never an easy thing to settle. But as hard as it is, it is still the responsibilities that UN carries in their mandate to bring world peace post world war 2. We live in crucial years here, dear readers, and it will be interesting how the UN tries to change the way it works, how they settle problems in the future. Because the worls is dynamic, its always changing, and it is the flaws of the UN in being conservative and traditionalists that makes them loose in the race for world peace.