A U.S. attack on Syria is unwise for several reasons. First, the United States has no vital strategic interests there. Bashar al-Assad's government is clearly a brutal dictatorship, but neither Democratic nor Republican presidents have cared about that before now. Instead, presidents from both parties have cooperated with the Assad regime whenever it seemed advisable to do so. More importantly, helping to topple the regime is likely to turn Syria into a failed state, igniting a struggle for power among competing sectarian factions. Some of these factions are deeply hostile to America and sympathetic to al Qaeda, which means that U.S. intervention could help bring some of our worst enemies to power.