Syria's civil war has been raging for 7 years and no end in sight

Kim Hjelmgaard | USA TODAY

Show Caption Hide Caption What is happening in the Syrian Civil War Foreign affairs reporter Oren Dorell explains who is fighting whom in the Syrian Civil War in two minutes.

News of an alleged gas attack against civilians in Syria marks the latest grim chapter in fighting that entered its eighth year in March. A conflict that began as a peaceful uprising against President Bashar Assad's regime escalated into a full-scale civil war that is now one of this century's deadliest.

Along the way, the Syrian conflict allowed Islamic State extremists to flourish, created the world's worst refugee crisis since World War II and exacerbated an international power struggle.

After seven years of relentless bloodshed, here is a recap of the crisis:

Why did the war start?

Economic problems and a lack of freedom caused resentment toward Assad's authoritarian rule. His forces responded to protesters in 2011 by killing hundreds of them and imprisoning many more as other pro-democracy uprisings known as the Arab Spring were taking place across the Middle East.

As public anger intensified, the growing chaos attracted extremist fighters throughout the region, including remnants of al-Qaeda in Iraq and an offshoot that became the Islamic State, or ISIS. Eventually, a full Syrian rebellion was mounted against Assad's regime. Some of these rebel groups started fighting each other as well as Assad's military forces because of sectarian divisions, complicating the situation.

What's the impact?

The numbers speak for themselves:

400,000 Syrians have been killed, according to United Nations estimates.



More than half of Syria's 20 million, pre-war population has been displaced.



5.5 million Syrians have fled abroad — 95% of them in just five countries (Turkey, Lebanon, Jordan, Iraq and Egypt), according to humanitarian groups.



400,000 civilians are trapped in opposition-held suburbs of Syria's capital Damascus as Assad's government wages a relentless bombing campaign to retake the area.



Of Syria's estimated 10 million children, 8.6 million are in dire need of assistance, up from about a half-million after the first year of war. Nearly 6 million children are displaced or living as refugees, and about 2.5 million are out of school.



About a third of Syria's housing and half of its educational and medical facilities have been destroyed, according to a 2017 World Bank report.

Which nations are involved?

The United States started arming and providing military air cover in 2014 for anti-Assad rebel groups who were also waging war against ISIS. Washington also began working with Syrian Kurds, one of the strongest partners in the fight against ISIS. After that support appeared to turn the tide against Assad, Russia — a longtime Syrian ally — entered the conflict in 2015 to shore up Assad's struggling regime. In addition, Russian President Vladimir Putin wanted to assert his country's power on the world stage.

Iran provided much-needed ground troops for the Assad regime, funneling money and fighters through the Lebanon-based Hezbollah militant group to further establish a strong presence in the region. Israel has been indirectly involved as it fears Iran could use Syrian territory to stage attacks on Israel or transfer weapons to Hezbollah. Iran is Israel’s arch-enemy and has sworn to destroy the country.

Turkey, Syria's northern neighbor, extended its ground operations into Syria, fearing the conflict could embolden Turkey's large population of Kurds to demand independence. In recent days, Turkish troops surrounded the Kurdish-held city of Afrin, forcing hundreds of civilians to flee.

With so many international forces operating in such close proximity, a danger exists that any mistake could trigger a larger conflict outside Syria.

What happens next?

Over the years, there have been various peace talks and United Nations resolutions calling for cease-fires to allow aid to reach areas where civilians were trapped. The cease-fires did not last or were violated. And most of the peace talks have stumbled on a major sticking point: the fate of Assad.

Mara Karlin, an intelligence and security expert at the Brookings Institution think tank, wrote in a February blog post, that "the fundamental debate for Washington going forward must focus on whether counterterrorism or broader geopolitical affairs should be the priority in Syria."

She noted that her congressional testimony in 2012 about Syria is still relevant.

The Syrian conflict "will not end with Bashar Assad voluntarily stepping aside, or choosing exile. It will not end with him making sufficient reforms to enable a transparent and free Syrian state. Let me be clear: continued oppression and violence in Syria will continue," she wrote in 2012.

Contributing: Alan Gomez

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