Like a weather vane, the recent visit to China by Saudi Arabia’s King Salman points to changing strategic directions in the Middle East-Asia security architecture. The significance of the Saudi monarch’s meetings with Chinese President Xi Jinping and other top officials goes well beyond the hefty $65 billion of economic and trade deals signed between Riyadh and Beijing. The visit confirmed the nascent strategic partnership developing between China and Saudi Arabia as Beijing seeks to promote stability along the trade routes of China’s 21st Century Maritime Silk Road, now threatened by the escalating violence of Iranian-backed rebels in Yemen.Although the first day of the Saudi monarch’s visit, March 16, 2017, grabbed international headlines with the signing of a $65b. Sino-Saudi trade and investment package, the 20-plus agreements on oil investment and energy largely follow the traditional transactional pattern of Sino-Saudi cooperation. King Salman’s visit to Beijing was truly noteworthy for cementing and advancing the strategic partnership established between China and Saudi Arabia during Xi Jinping’s January 2016 visit to Riyadh. Three days prior to the Saudi monarch’s visit, China’s Foreign Ministry declared, “We stand ready to take King Salman’s visit as an opportunity to take [the] China-Saudi Arabia comprehensive strategic partnership to a higher level.” King Salman reciprocated with his declaration in Beijing that “Saudi Arabia is willing to work hard with China to promote global and regional peace, security, and prosperity.”The source of China and Saudi Arabia’s increasing alignment of interests is China’s effort to create its self-declared 21st Century Maritime Silk Road – a China- to-Europe maritime commercial transportation corridor consisting of a series of Chinese-built port installations extending westward across the Indian Ocean and then via the Red Sea and Suez Canal to the now Chinese- owned Pireaus seaport, on Greece’s Mediterranean coast. Having heavily invested in Piraeus to transform it into one of the world’s state-of-the-art container ports, Beijing now owns and operates one of the European Union’s major seaports as the MSR’s main outlet point for Chinese goods to enter European markets.The single greatest threat to China’s economic interests in creating and preserving the reliable and cost-efficient flow of commerce across the MSR is Iran. Overall, Beijing maintains a careful balance between its relations with Iran and its relations with Saudi Arabia.In January 2016, Xi Jinping visited both Riyadh and Tehran, where he and his Iranian counterpart agreed to a 10-year program to raise Chinese-Iranian bilateral trade to $600 billion. Nevertheless, Tehran’s effort to expand its sphere of influence to the Gulf of Aden-Red Sea corridor through its proxy war against Saudi Arabia in Yemen and the Horn of Africa represents a disruption to the maritime security domain that China cannot tolerate. In January 2016, Beijing declared its support for Yemen’s efforts to defeat Iranian-backed Houthi rebels.Two weeks after Beijing’s declaration for Yemen’s government, Houthi rebels supplied with Iranian technology attacked a Saudi frigate with an improvised “drone” attack boat, a remote-controlled boat laden with explosives.Iran has continued to escalate its support to Houthi rebels with the provision of more sophisticated weapons technology including the transfer of Iranian aerial drones and quite likely anti-ship missiles. On March 10, a Yemeni coast-guard vessel was destroyed in the narrow Bab el-Mandeb strait between the Gulf of Aden and the Red Sea. In response to the maritime threats, China is constructing of its first overseas base in Djibouti, which strategically straddles the Gulf of Aden and the Red Sea on the shore opposite Yemen in the Bab el-Mandeb Strait.Just prior to Xi Jinping’s January 2016 visit to Saudi Arabia, Djibouti formally severed diplomatic relations with Tehran and then signed a security cooperation agreement with Riyadh. Saudi Arabia is currently finalizing arrangements with Djibouti for the establishment of a Saudi base in addition to the Chinese naval base that will have the capacity to house 10,000 personnel.The Sino-Saudi agreement to collaborate on drone manufacturing signed during King Salman’s Beijing visit serves as another indication that the two countries may be looking to their strategic cooperation to contain Iranian activities in Gulf of Aden-Red Sea corridor.China’s acceptance of Saudi Arabia’s interventions in a vital sea lane of the MSR and Saudi Arabia’s embrace of China as potential security partner signals a consequential shift in the Middle East-Asia security architecture.Any further escalation of Iran’s proxy wars in the Gulf of Aden-Red Sea corridor is likely to drive Beijing and Riyadh close together as strategic partners for maritime security.The author is a Fellow at the Truman Research Institute for the Advancement of Peace, The Hebrew University of Jerusalem. Follow him @michaeltanchum. An earlier version of this article first appeared in East Asia Forum.