US involvement in Syria since 2011
Here is a recap of Washington's involvement in the Syrian conflict, following US President Donald Trump's announcement on Sunday that Islamic State group leader Abu Bakr al-Baghdadi killed himself during a US military operation.
Pressure on Assad
On April 29, 2011, a month after the first protests in Syria that were met with brutal force by the regime, Washington imposes sanctions on several Syrian officials. The measures extend to President Bashar al-Assad the following month.
On August 18, US President Barack Obama and Western allies for the first time explicitly call on Assad to stand down.
In October, the US ambassador leaves Syria for "security reasons". Damascus recalls its ambassador from Washington.
Obama backs off 'red line'
In August 2013, the Syrian regime is accused of carrying out a chemical attack near Damascus that killed more than 1,400 people, according to Washington.
Despite having vowed to act with force if Syria crossed the chemical weapons "red line", Obama at ...