Last week, a five-man cell from al-Shabab, al-Qaida’s Somalia-based affiliate, entered the popular 14 Riverside hotel-office complex in an affluent neighbourhood of Kenya’s capital, where there were more than 700 workers and hotel guests. One of the men blew himself up with a suicide vest, while the four others threw hand grenades and fired on people having a late lunch and then trying to flee.

Al-Shabab has wreaked havoc in East Africa since 2006, proving to be one of the world’s deadliest jihadist groups. Its latest attack in Nairobi was an appalling reminder that, despite historic reforms and rapprochement between old foes in the Horn of Africa, terrorism remains a major threat for Kenya and the region. 

Amid the chaos in Nairobi last week, the response from Kenya’s security forces, which have been credited with improved counterterrorism capabilities, kept the death toll relatively low at 21, plus the five attackers who were killed. Among the dead were 33-year-old Abdalla Dahir and 31-year-old Feisal Ahmed, both Somali-Kenyans employed by the Somalia Stability Fund, which has worked to help Somalia recover from decades of civil and state collapse that have pushed it to the bottom of most development indicators. An American citizen, Jason Spindler, 41, was also among the victims; he was working on Wall Street as an investment analyst on 9/11 and had survived the attack on the World Trade Center.
The Nairobi attack could reinvigorate the al-Shabab and al-Qaida brands at a time when the Islamic State has been attempting to make inroads into Somalia. The attack, though, doesn’t necessarily signal new capabilities for al-Shabab. Its strategy remains mostly a “composite insurgency,” with different factions that support, tolerate or cooperate with each other to varying degrees, largely for resolving day-to-day issues in Somalia like land disputes, rather than over a shared higher purpose.

Kenya, of course, is no stranger to terrorism. In 1998, al-Qaida orchestrated bombings of the U.S. Embassy in Nairobi and in neighboring Tanzania that killed more than 200 people. In 2002, al-Qaida sympathizers hit an Israeli-owned hotel on Kenya’s coast. Attacks inside Kenya rapidly increased after the Kenyan Defense Forces launched operation Linda Nchi—“Protect the Country” in Kiswahili—in October 2011, which saw 2,000 soldiers cross the border into Somalia to create a “buffer zone.” U.S. diplomatic cables from February 2010, released by WikiLeaks, revealed that American officials strongly opposed Kenya’s intervention and offered a litany of reasons why it was a bad idea, including that it “would more likely add to Somalia’s instability than to help stabilize the country.”
Since then, al-Shabab has launched hundreds of raids into Kenya’s border areas and staged major attacks deeper in the country, killing 67 people in Nairobi’s Westgate Mall in September 2013, 60 people in the predominantly Christian town of Mpeketoni in June 2014, and 147 faculty, students and staff at Garissa University in April 2015. Meanwhile, inside Somalia, Kenyan troops have suffered significant losses in numerous al-Shabab attacks, including on two military bases in el-Adde in January 2016 and in Kulbiyow in January 2017. The massacre at el-Adde has been called Kenya’s worst military defeat in the country’s history.
Kenya’s foreign policy in Somalia remains opaque. Nairobi is considered a stable center in the Horn of Africa, a region riddled with conflicts and humanitarian and environmental crises. Nairobi hosts the third-largest United Nations office in the world, is popular with NGOs and diplomats serving the neighboring fragile states, and has recently seen the arrival of several multinational corporations looking to tap into emerging African markets. Attacks like this latest one hurt Kenya’s economy, in particular the tourism sector, which earns roughly $1 billion a year in revenue and generates thousands of jobs—many of them in poor, marginalized areas considered vulnerable to radicalization, like the Kenyan coast where al-Shabab has found recruits.

The fact that last week’s attack came at a time when historic changes are underway in the Horn of Africa puts a damper on the recent sense of optimism across the region. A year ago, Ethiopia’s government declared sweeping reforms in response to anti-government protests. Ethiopia also announced a rapprochement with its erstwhile arch-enemy, Eritrea. The tectonic shifts in Ethiopia and its relations with its neighbors could eventually lead to a more democratic and stable Ethiopia and wider Horn of Africa. But there is still a long way to go, as entrenched Ethiopian interests, from ethnic disputes to military factions, fight to preserve the status quo. These changes affect Somalia, the focal point for every state in the Horn of Africa, which all want to contain al-Shabab but don’t often agree on how to do it and have struggled to leverage international support. 
Amid mounting geopolitical competition in the Red Sea, there has been nascent cooperation between Somalia, Ethiopia, Eritrea and Djibouti, designed to improve lucrative port access and commercial development. Oil-rich Gulf countries are spending big, pursuing regional interests that are reshaping traditional spheres of influence and also exacerbating fault lines.
The 14 Riverside attack was proof of al-Shabab’s ability to go undetected and its willingness to strike Kenya, even as it continues its deadly work inside Somalia. The fallout for Kenya and its international security partners, including the United States, could be hefty, eroding the economic and security gains made since the last major attack in Nairobi five years ago. For the rest of the Horn of Africa, al-Shabab remains a symptom of Somalia’s instability, something the current reform drive in the region cannot overlook.