At first glance, the United Arab Emirates might look like it is Saudi Arabia’s wingman when it comes to regional security. After all, the UAE has joined Saudi Arabia in a number of regional ventures in recent years. Together, they intervened to stabilize the monarchy in Bahrain after popular protests erupted in 2011, and have spent billions of dollars backing Egyptian President Abdel Fattah el-Sisi’s government since 2013. Most recently, the UAE joined the ongoing Saudi coalition intervening against the Houthis in Yemen.

But appearances are deceiving. Despite having joined these Saudi-led initiatives around the Middle East since the start of the Arab Spring, the UAE is not a mere satellite of Saudi Arabia, acting at Riyadh’s command. Rather, they share common political and security interests—particularly when it comes to threats they perceive from Iran and Islamist groups. So it’s not surprising to see Riyadh and Abu Dhabi working together to support el-Sisi in Egypt or suppress Iranian-backed Houthi rebels in Yemen. ...