In the south of Yemen, secessionist groups affiliated with the self-proclaimed Southern Transitional Council (STC) and forces aligned with the internationally recognized government are clashing for territorial control in Aden and other southern governorates. Although nominally allied against the Houthis, the northern Shia insurgents supported by Iran, the two forces have been battling since August 2019. STC-aligned forces stormed the presidential palace of Aden on August 10, where President Hadi and internationally recognized institutions had been based since fleeing Sanaa following Houthi advances in 2015. The showdown targeted the palace (although Hadi does not reside in it) to undermine the legitimacy of these recognized institutions. In response to the attack, Saudi Arabia and the United Arab Emirates (UAE), for the first time, used air power to defend their Yemeni allies on the ground. After the STC seized the presidential palace, Saudi-led airstrikes targeted secessionists’ positions in Aden. The Emiratis bombed pro-government forces on August 29, claiming “self-defense” against imminent terrorist attacks.

This military infighting—as southern militias are all ostensibly part of the formal Yemeni military—mirrors the struggle for Yemen’s future institutional structure. Since 2015, rivals continue disagree about whether Yemen should be a unified state, a partitioned one, or a federal government. The anti-Houthi front was formed despite these existing schisms. However, these contradictions and divergences can no longer be sustainable. After four years of fighting, the deep fragmentation within Yemen’s formal military and the Saudi-led coalition has now reached a breaking point.  

Geographical and ideological differences deepen the military conflict. Due to the 1990 north-driven unification and the south’s defeat in the 1994 civil war, northern officers and soldiers have since dominated the army’s composition. The southerners were thus largely kept out from the unified military. Yemen’s army soldiers have a tribal background and, in many cases, belong to the Hashid tribal confederation, of whom Saleh and the Al Ahmar family are part. They also share ties with the Yemeni Congregation for Reform (Islah), the party affiliated with the Muslim Brotherhood and the tribal-conservative milieu. Capitalizing on his web of Islamist tribal-military loyalties in Mareb and al-Jawf, General Ali Mohsin Al Ahmar became vice president and deputy supreme commander of the armed forces for President Abd Rabu Mansur Hadi. Since President Hadi was formerly Saleh’s vice president, southerners mostly perceive him as a defender of northern interests, although he comes from the southern region of Abyan. 

Moreover, a hate legacy since the 1986 intra-southern civil war is still alive and affects current military balances.  The STC leadership comes predominantly from Lahj and al-Dhale, the regional factions that defeated Abyan and Hadi in 1986. Conversely, STC-aligned forces seeking secession rally local fighters on a regional basis, thus establishing a direct connection with their respective theatres of operation. The Security Belt Forces (SBF)—which are deployed in Aden—Abyan Lahj, and al-Dhale, recruit mostly from the large Yafei tribal confederation, as the Shabwani Elite Forces (SEF) recruit from Shabwa and the Hadhrami Elite Forces (HEF) from Hadhramawt. These forces have formed the backbone of the STC since 2017, when Aden’s former governor Aydarous Al Zubaidi founded the council to give an institutional representation to the southern separatist cause. These military groups include armed Salafis, socialists, and sympathizers of the former People’s Democratic Republic of Yemen (PDRY), all of whom share secessionist beliefs.  

Saudi Arabia and the UAE have supported rival southern Yemeni players since the beginning of the intervention.  Although the UAE purportedly supports Hadi’s recognized government, it has organized, trained, equipped, and paid the SBF, SEF and HEF to provide local security since mid-2015. This reflects the parallel strategies adopted by Saudi Arabia and the UAE since the start of the intervention. Saudis have focused on the north to contain the Houthis’ expansion mainly through bombing campaigns. Meanwhile, the Emiratis have led ground-operations in the south to prevent the Houthis’ penetration and counter al-Qaeda activity in the Arabian Peninsula (AQAP).

Intermittent skirmishes have previously erupted in the south. In Aden, clashes broke out in April 2017 for control of the airport. In January 2018, pro-government forces prevented the STC from holding a rally in the city, and approximately 40 people were killed during street fighting. However, these clashes reveal deep fissures and represent a game-changer in Yemen’s political and military balances. The current crisis underscores a number of contradictions within Yemen’s military. All the forces involved in ground fighting nominally support President Hadi and the internationally recognized government. In fact, the STC-aligned armed groups still claim to side with the government, although their recent political statement states, “the goal of the people of the south to restore the independent federal state of the south is an irreversible and irrevocable choice.” Rival forces in the south all belong to the formal military, since by the recognized government institutionalized southern militias later. In Aden, the Presidential Guard, an elite army unit protecting President Hadi and led by his son Nasser, fights against the SBF who were formally brought under the authority of the ministry of interior in late 2016. In the same way, the Elite Forces of Shabwa was integrated within Yemen’s army in 2016 as the HEF, and the SEF now clashes with the 21st Brigade of the army in Ataq, the capital of this oil-rich governorate. Neither the army nor the secessionist forces are coherent blocs. The army coalesces around two military oligopolies: President Hadi (in the Abyan governorate) and his Vice President Ali Mohsin (in the Mareb governorate). Both had roles in the old regime: Hadi is a southerner who joined the northern-driven power led by Saleh, and Mohsin is a northerner who enforced the Sanaa-rule in the south. Furthermore, secessionist forces are divided internally due to clashing local identities, disproportionate access to natural resources, and conflicting interests. For instance, Hadhramawt is practically heading towards de facto autonomy from central institutions. Its considerable oil, gas, and water resources allow the governorate to promote local governance mechanisms (bank and remittances), while also building on traditional ties with Saudi Arabia and the Hadhrami diaspora. 

Aden’s clashes are yet another crisis that has faced Yemen’s military since the 2011 uprising.  The factionalism and shifting alliances that have defined Yemeni politics have spread to its army. In 2011, the anti-government protests broke the army into two rival factions. One faction was in support of the former president Ali Abdullah Saleh, who resigned in late 2011. The other faction— led by General Ali Mohsin Al Ahmar and the prominent Al Ahmar family (not related to General Ali Mohsin)—was against him. In 2014 and 2015, the Houthi insurgency exacerbated these cleavages: the Houthis consolidated an alliance of convenience with the military faction still loyal to former president Saleh in order to derail the Hadi-led political transition. 

The military’s growing fragmentation weakens the anti-Houthi front, thus increasing risks for Saudi national security. To address this, Saudi Arabia has been brokering indirect talks between government and secessionists in Jeddah, with the goal of rebuilding Yemen’s security sector. Khalid bin Salman Al Saud, the Saudi deputy defense minister and younger brother of Crown Prince Mohammed Ben Salman, recently stressed the urgency “to unify ranks and voices” against common threats like the Houthis and AQAP. However, the STC has reportedly rejected the inclusion of its forces under the authority of the recognized government. A variety of intertwined variables, such as local identities, ideology, past legacies, and external backing, complicates conflict resolution efforts in the south. The military’s current crisis reflects these fissures and mirrors fault lines. De-escalation and reconciliation efforts in the south should take into consideration the post-2011 security picture and its impact on the military—after all, factionalism and alliances of convenience produced Yemen’s current southern escalation. If these political contradictions are not addressed, new military rifts are likely to emerge resulting into further fragmentation. 

Eleonora Ardemagni is an associate research fellow at the Italian Institute for International Political Studies (ISPI), teaching assistant at the Catholic University of Milan, and an analyst for the NATO Defense College Foundation and Aspen Institute Italia. Follow her on Twitter @ispionline.