Why did the US decide to go to war in Iraq without UN support?

The U.S. decided to go to war in Iraq in 2003 primarily due to concerns over weapons of mass destruction (WMDs) that the Iraqi regime, led by Saddam Hussein, was believed to possess. The U.S. government argued that Iraq's failure to comply with UN resolutions and its perceived threat to regional stability justified military action, despite lacking explicit UN support. Additionally, the Bush administration sought to promote democracy in the Middle East and counter terrorism, framing the invasion as part of a broader strategy in the post-9/11 context. Ultimately, the decision reflected a belief in the necessity of unilateral action when multilateral options were seen as ineffective.