BBC: The UK-based Syrian Observatory for Human Rights said 17,790 of the dead were civilians, including 3,501 children.
Much of the violence comes as a result of advances by Islamic State and other militants groups in the two countries.
US-led air strikes against Islamic State (IS) militants, fighting between government troops and rebels in Syria, and sectarian violence in Iraq have also accounted for large numbers of deaths… (more)
EDITOR: To conceptualize this, it helps to imagine everyone at an Eagles football game being killed. Horrible. Yet there is little the USA and others can do about what amounts to a three way civil war.
