IN 2014 part of the rebels broke off to make their own group called the Islamic State of Iraq and Syria ( ISIS), mostly made up of Jihadist extremists that Assad released to fight against him so that outside countries would have a harder time supporting the rebels. This group became very barbaric and became a threat to anyone who involved themselves with them. Many of them trained because the U.S. trained rebels to fight against Assad but this was before ISIS was an issue.
Why is this war happening?
Many people in Syria are unhappy with the government form and decide to start protesting against the current government and they want a democracy. The President denies the request to reform the government and the protests get more intense and the Syrian army has to handle them with violence causing the protesters to rebel and fight back hence the name, Rebels.
The U.S. became involved in the war when Assad began taking extreme actions to deal with rebels while also killing many of innocent civilians with chemical weapons. Once this happened the U.S. began to train rebels and even threatened to use missle strikes on Assad's regime
Effects outside of Syria
With the fighting happening in most peoples everyday lives, the risks from just living in Syria are very high. Hundreds of thousands of people have fled to nearby countries like Turkey for example has the largest amount of refugees flowing into their country. This flow could continue to happen as long as the war does, but there is no end in sight for either.
Along with the refugee crisis the fighting has spread to other countries like Israel which has previously been in a war with Syria. With the fighting spreading Israel is fearing the birth of another war with Syria, but with Russia now backing Syria there could be more cons to come from fighting than there would be pros because of the risk of having such a powerful country against them.
No End in Sight
With powerful countries backing smaller groups and smaller countries there could be a bigger war emerging from this civil war. Also with so many groups that are fighting more than one group and even some groups not really sure who they are for or against followed by the larger powers funding them and training them there could be no end anytime soon.