Last year, the UN's peacekeeping army of 112,000 troops suffered 132 combat deaths. More than ten times that number were wounded, injured in accidents or disabled by disease. The peacekeeper combat fatalities come out to about 118 dead per 100,000 troops per year. In Afghanistan, foreign troops are losing about 350, and at the peak of the fighting (2005-7) in Iraq, the losses were 500-600 per 100,000. The rate for U.S. troops in Vietnam and World War II was about 1,500 per 100,000 troops. So the UN peacekeepers are often seeing some considerable violence, but at less than a third of the rate of troops in actual wars.
Meanwhile, the UN is having trouble getting more troops for its peacekeeping force. While the casualties have something to do with this, corruption, and lack of success, are more often discouraging countries from contributing their troops. The corruption angle is interesting, as it pertains both to the corruption within the UN bureaucracy, and the corrupt atmosphere the peacekeepers operate in, and often succumb to. Casualties are expected, but the contributing countries feel a lot of their troop losses are the result of restrictive UN rules that limit what peacekeepers can do. This, in turn, is believed most responsible for a lack of success for the peacekeeping missions.
For some time, most of the peacekeeping troops have come from India and Pakistan. These two nations are not happy with the lack of volunteers from other major nations. The chief reasons for that are the same ones annoying the current peacekeepers (corruption and restrictive rules of engagement). In addition, the major military powers (with the exception of China and Russia) feel they already contribute quite a lot in the form of money to pay the peacekeepers. And the contributors are also upset at the lack of results.
The UN will spend about $7 billion on fifteen peacekeeping operations this year. This pays for a force of over 112,000 troops and support staff. It's actually a pretty cheap way of keeping some conflicts under control. The causes of the unrest may not be resolved by peacekeepers, but at least the problem is contained and doesn't bother the rest of the world too much. This is an increasingly unpopular approach to peacekeeping, except in the UN bureaucracy. Many UN members would rather send peacekeepers to where they are not wanted (by the government, usually a bad one, that is often the cause of the trouble in the first place.)
Most of the money is going to a few large peacekeeping operations. Three of the largest get over half the cash. Thus the Congo operations get 17.5 percent of the money, Darfur (western Sudan) gets 22 percent and southern Sudan gets 12 percent. Africa has the largest number of "failed states" on the planet and, as such, is most in need of outside security assistance. The Middle East is also a source of much unrest. But there the problem isn't a lack of government, just bad government. Most Middle Eastern nations are run by tyrants, who have created police states that at least keep anarchy at bay.
To further complicate matters, religion has become a touchy subject. While Islamic radicalism is more of a problem to fellow Moslems than it is to infidels (non-Moslems), most Middle Eastern governments avoid blaming Islam for these problems. Since it's increasing difficult to pin the blame on "colonialism" or "crusaders," the Middle Eastern nations encourage other UN members to just stay away from the religious angle altogether. This has made it difficult to deal with peacekeeping issues in Moslem nations, since religion usually plays a part in creating the problem. To the UN, this is just another diplomatic problem to be dealt with, not very well.
But overall, the troops and money that keep all the peacekeeping going are in danger of fading away. Frantic diplomacy is underway by the UN to try and makes things all better, but success is not assured.