AbstractSaudi Arabia and the United Arab Emirates (UAE) have pursued distinct policies in Yemen since their intervention began in March 2015. The Saudis remain mired in an air war in the north to defeat the Houthis, an Iran‐linked group that ousted Yemeni President Abdu Rabbu Mansour Hadi. Between 2016 and 2019, the UAE shifted from this task toward a ground war in the south to fight Islamist groups and support the Southern Transitional Council (STC), a secessionist organization that opposes Hadi's government. Why have Saudi Arabia and the UAE pursued such different intervention policies? Building on Elizabeth Saunders’ intervention typology, as well as theories of alliance politics, I analyze individual‐leader perceptions of both the origins and types of external threats. I argue that Saudi Crown Prince Mohammed bin Salman formed a “nontransformative” policy in the north to address a material threat embodied in the Houthis. Alternatively, Abu Dhabi Crown Prince Mohammed bin Zayed formed a “transformative” policy in the south to counter Islamist threats that could spread to the UAE. Assessing these different intervention policies amid divergent threat perceptions sheds light on Yemen's multifaceted conflict.