Analysis: Who's backing who as Syria's civil war threatens to spread
Slideshow: Syria uprising
By Mandy Clark and Paul Nassar, NBC News
Syria’s two-year civil war has claimed more than 100,000 lives and sent at least 1.7 million refugees spilling across its borders.
It has already affected neighboring countries, and now threatens to drag in the United States.
What began as a popular movement, demanding the removal of autocratic President Bashar Assad, has become an increasingly sectarian conflict.
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