The United Nations is constantly embroiled in brutal conflicts, but some do it vastly more political harm than others. The organization has never fully recovered from its failure to prevent the Rwandan genocide and Srebrenica massacre in the 1990s. Now it faces simultaneous crises in South Sudan and Syria that may do it equally severe damage. In South Sudan, peacekeepers have been thrown off balance by an outburst of violence for the second time in three years. The U.N. mission (UNMISS) there was unable to stop the country collapsing into civil war in 2013, but managed to protect tens of […]