Photo: Jemal Countess | Getty Images

Today marks the 20th anniversary of US troops advancing on Baghdad during the 2003 invasion of Iraq.

In the two decades since the overthrow of Saddam Hussein, sectarian divisions that were largely repressed during the Sunni-dominated Ba’athist government have resurfaced and heavily shaped politics in Iraq. As a result, the country has experienced several periods of protracted instability tied to sectarian and ethnic divides. This was seen most recently in a year-long government formation process following 2021 parliamentary elections.

Iraq’s Shia majority has seen its political power grow significantly since 2003, causing neighboring Shia Iran to steadily expand its influence over Baghdad. As a result, numerous Iraqi political parties and armed groups now have direct links to Tehran. Many Sunnis have firmly opposed Iran’s activities in Iraq, further inflaming sectarian tensions.

As demonstrated by recent political and security challenges, Iraq will likely remain impacted by the unintended consequences of the US-led invasion. Iraq’s Shia edge and  lacking US will to seriously reengage in Iraq will mean Iran will likely remain the most influential external force there in the medium-term. The continued Iranian presence, rejected by Sunnis and Kurds, will likely perpetuate sectarian divisions and only further destabilize the troubled fledgling democracy.