The ousted president, Abd-Rabbouh Mansour Hadi, was a highly cooperative US counter-terror partner, and the UN had dispatched a special envoy entrusted with shepherding the country's fragile transitional process. These efforts failed to prevent the full-on state collapse that Iranian-backed Houthi rebels finally completed on Friday.
But the biggest loser from the Yemeni government's fall is Sa'ana's wealthy, powerful, and perpetually insecure neighbor to the north: Saudi Arabia. In recent years, Saudi policy towards Yemen has been built around the need to stabilize the government in Sa'ana while sealing off the two countries' over 1,000-long and minimally policed frontier.
Saudi Arabia was a major financial backer of the transitional government. The country's monarchy feared that a collapsed Yemen would exacerbate the threats posed by both Al Qaeda in the Arabian Peninsula, the powerful Yemen-based Al Qaeda branch, as well as the Houthis, Shi'ite militants allied with Iran, which is still Riyadh's top geopolitical rival.