The war in Syria has killed hundreds of thousands and displaced millions of civilians -- turning the country into fertile ground for ISIS militants to seize territory.

Syria’s President Bashar al-Assad is connected to thousands of civilian casualties and has used chemical weapons against his own people. Last night, President Donald Trump authorized U.S. forces to launch 59 tomahawk cruise missiles at a Syrian air base in response to the chemical weapon attack.

A look at the current state of Syria:

Assad Regime

Syria has been ruled by the authoritarian Assad regime since 1970. Assad was originally touted as a potential reformer, his part in the crackdowns on Arab Spring protesters, which led to the Syrian Civil War, brought calls from the EU and U.S. for him to stand down. President Obama first called for Assad to step down in August 2011. Russia began military action to prop up the Assad regime in Syria in September 2015.

Civil War

Civil war broke out in Syria in March 2011 amid nationwide protests calling for President Assad’s resignation. Government security forces attacked protesters, inciting opposition supporters to take up arms. Since the war began, almost 5 million Syrians have fled the country and 465,000 people have been killed or are missing. The United Nations estimates there are currently 13.5 million people in need of humanitarian assistance in Syria.

Russian Support

Russian military support for Syria dates back to the 1950s during the height of the Cold War. Russia is Syria's largest arms supplier with at least $3.4 billion in weapons deliveries since 2008. The Russians have vetoed seven U.N. Security Council resolutions against Syria since the conflict began in 2011. The Russian military began airstrikes in support of the Assad regime in September 2015.

Chemical Weapons

There have been approximately 10 chemical attacks carried out in Syria since 2013. At least four chemical attacks on civilians are connected to the Assad regime. Obama warned Assad the use of chemical or biological weapons would cross a "red line" for the U.S. in 2012. The largest-scale use of chemical weapons to date was reportedly a nerve gas attack in August 2013 which the U.S. estimated killed over 1,400 people - the attack has been blamed on the Syrian government.

U.S. Involvement

The U.S. is the largest bilateral provider of humanitarian assistance to the crisis, providing almost $6 billion since 2011. The U.S. and coalition forces began conducting airstrikes on ISIS in Syria in September 2014. U.S. special operations forces have been on the ground in Syria since November 2015.

Sources compiled by Fox News Research, Associated Press