Soldiers of the Somali National Army during a joint operation with AMISOM to recapture territory held by the al-Qaeda-affiliated extremist group al-Shabaab, May 24, 2012. AP September 21 began like any other Saturday morning at the upscale Westgate Mall in Nairobi, Kenya. Parents brought their excited youngsters to a children’s party; Kenyan elites patronized the gourmet restaurants; customers perused the merchandise in the mall’s expensive boutiques; and tourists and expatriates soaked in the international ambiance.

Then at 11:30 am, havoc broke out. Ten to 15 heavily armed militants stormed the mall through multiple entrances, throwing grenades and opening fire on security guards and shoppers alike.

The siege created a bloodbath that killed over 60 people and left the building littered with mutilated bodies. The gunmen took hostages, shot women and children point-blank, cut off body parts, and tortured and executed those they considered non-Muslims and infidels. Thus began a four-day siege.

It was a far cry from other al-Shabaab attacks in Kenya, which have generally consisted of drive-by shootings, small arms fire, or the lobbing of grenades at civilian and security targets. Although such attacks have become increasingly frequent since 2011, nothing of this magnitude was imaginable just weeks ago.

The massacre accordingly represents al-Shabaab’s savage coming of age as an international terrorist organization. Kenya and its allies must respond by strengthening regional security operations, reaching out to moderates, and cutting off the group’s sources of funds.

Messages of the Massacre

Far from a straightforward crime scene, the massacre at Westgate Mall sent several symbolic messages. Westgate Mall is located in Westlands, a diverse upper-middle class neighborhood that is home to a large expatriate community. The mall is partly owned by an Israeli and has many Israeli-owned stores, such as the popular Art Cafe, where many were killed during the raid.

Police check the site of an attack at the Paradise Hotel in Kikambala, Kenya, Nov. 28, 2002. Three suicide bombers attacked the Israeli-owned hotel, killing eight other people, and at least two missiles were fired at, but missed, an Israeli airliner taking off from Mombasa airport in simultaneous attacks. AP Terrorist activities in Kenya often target institutions connected to Israel due to their symbolic value. In 2002, for instance, militants launched two simultaneous attacks on Israeli targets, including a car bomb at the Israeli-owned Paradise Hotel in Mombasa that killed 15 people, including three Israelis. Such attacks act as a tool of mobilization and garner Western media attention.

However, the over-riding message of the Westgate attack, launched by the Somalia-based al-Qaeda affiliate al-Shabaab, was retaliation for Kenya’s 2011 invasion of Somalia.

Kenya sent troops into Somalia after a series of cross-border attacks by al-Shabaab militants. The goal was to expel the militants from the border region and create a buffer zone between the militants’ strongholds in southern Somalia and Kenya. The Kenya Defense Forces successfully pushed the militants out of the border region and now control a swath of territory inside Somalia.

The Westgate attack, therefore, was designed to send a message that al-Shabaab was still alive and deadly despite the setbacks of the last two years.

During the siege, the group taunted Kenyan authorities in frequent social media messages. Those messages also warned the West to expect similar attacks if it did not withdraw support for the African Union’s (AU) military operation in Somalia, where it has already expelled the militants from major cities such as Mogadishu and their southern stronghold Kismayo.

Kenyan president Uhuru Kenyatta, who lost a nephew in the massacre, said that Kenya remained resolute and would not pull its troops out of Somalia, where they are participating in the AU mission. During a Mashujaa Day celebration on October 20th, he reiterated his government’s right to intervene abroad. “From time to time,” he argued, “we may be required to intervene externally to keep our country, and our neighbors safe.”

Going International

In turn, the well-planned and well-funded Westgate attack indicates that al-Shabaab has set its sights on international targets. This is telling, because it means that the internationalist faction has won the power struggle within al-Shabaab. Led by Moktar Ali Zubeyr, also known as Ahmed Godane, this faction has marginalized the nationalist wing that preferred to focus on overthrowing the government of Somalia rather than engaging in international terrorism.

Godane, who is thought to be in his thirties, consolidated his power within al-Shabaab after the killing of the al-Qaeda militant leader Aden Hashi Farah in a 2008 U.S. airstrike on Somalia. Under Godane’s direction, al-Shabaab imposed a brutal Sharia regime marked by beheadings, stonings, and amputations for minor infractions.

In 2012, Godane pledged allegiance to al-Qaeda’s leader Ayman al-Zawahiri and ruthlessly eliminated his rivals in the organization. The latest casualty in the power struggle within al-Shabaab is the American-born Omar Al-Hammami, sometimes known as al-Ameriki. Hammami was one of al Shabaab’s most prominent foreign-born leaders. He was expelled from the organization after some disagreements with the leadership over issues related to Godane’s extreme implementation of Sharia law. His execution was part of a clean-up operation that consolidated Godane’s rule.

In July, the UN Monitoring Group on Somalia and Eritrea warned that although al-Shabaab had lost ground militarily, it had “shifted its posture to asymmetrical warfare” in urban and rural areas. The monitoring group’s report warned that the group had maintained its core military strength by avoiding direct confrontations with the African Union Mission in Somalia (AMISOM) and government forces. Its 5,000-strong force remained intact in terms of “operational readiness, chain of command, discipline and communication capabilities.”

The UN report also noted that Ahmed Godane’s leadership has gone unchallenged despite internal dissent. Godane has maintained an iron grip on the organization through his ruthless “secret service,” Amniyat. The report concluded that al-Shabaab continues to pose a regional and international threat through affiliates such as al-Hijra, an offshoot of the Muslim Youth Center — a terror group that had been disrupted by local and international security operations. Al-Hijra is regaining strength partly by sending its recruits for training in Somalia, after which they return to conduct operations in Kenya.

A soldier serving with the Kenyan Contingent of the African Union Mission in Somalia (AMISOM) stands guard while a combat engineering team sweeps the area for unexploded ordnance and improvised explosive devices (IEDs) in the southern Somali port city of Kismayo. AP Al-Shabaab’s new internationalist political ideology has also attracted jihadists from abroad who are interested in attacking Western targets in the region. The group boasts that it has recruited over 100 Britons and 40 Americans into its ranks — and indeed Kenyan government officials have suggested that several Americans and possibly a Briton were among the terrorists attacking the mall. There are also reports of al-Shabaab’s collaboration with other al-Qaeda affiliates, including those in Yemen and North Africa.

The massacre at Westgate is particularly revealing because many prominent Somalis with ties to al-Shabaab have extensive investments and properties in Kenya. They live and run lucrative businesses in Nairobi and other major cities. These business ties between prominent Somalis and Kenyans have deterred major attacks within Kenya for years. The fact that al-Shabaab chose to launch a major attack in Nairobi means that the organization no longer feels beholden to these businessmen and has found new sources of funding, weapons, and logistical support.

Mumbai Model

The spread to new countries in part reflects al-Shabaab’s growing weakness within Somalia, where it has lost considerable ground since 2010. Yet it also shows that the group still has the ability to conduct deadly attacks abroad by using small bands of highly trained and motivated militants. This is the approach that was deployed successfully by groups staging terror attacks in Mumbai, London, and Madrid, and has come to be known as “the Mumbai model.” In Mumbai in 2008, a handful of lightly armed militants attacked several landmark sites, after which they stormed a popular international hotel where they slaughtered dozens and held the building for days before Indian security forces could retake control.

The Mumbai model involves a direct threat to soft targets such as malls, schools, hospitals, and other lightly guarded public facilities. In late September, for example, Nigeria’s Boko Haram, a terrorist group that shares al-Shabaab’s Islamist ideology, slaughtered over 30 sleeping students in a college dormitory. As far back as January 2013, Kenyan intelligence had warned that al-Shabaab was planning a “Mumbai-style” operation targeting landmarks such as Westgate Mall and Holy Family Basilica, a Roman Catholic cathedral in Nairobi.

The Boko Haram raid and the Westgate Mall attack have eerie similarities. In both, a small group of militants wielding small arms and grenades stormed a public facility, took hostages, and massacred civilians. This model could easily be exported to the West. The frequent mass killings by individuals in the United States demonstrate the ease with which a group of dedicated militants could cause mayhem.

Statement of Intent

The fact that the terrorists spared Muslims (or tried to) at the Westgate Mall suggests that their intention was to destabilize Kenya. They aimed to provoke the Kenyan government into overreacting by indiscriminately targeting and humiliating Muslims, who constitute about 10 percent of the population. Kenya has a history of cracking down on Muslims generally, and Somalis in particular, after such incidents. In al-Shabaab’s logic, such a crackdown could potentially turn Muslims against the government and radicalize a significant portion of the population.

There is some evidence to support that conclusion. For example, just days after the Westgate Mall massacre, youth in the coastal city of Mombasa rioted for days in response to the drive-by shooting of a popular Muslim cleric associated with al-Shabaab, Sheikh Ibrahim Ismail. He had become the most prominent radical preacher after the killing of his mentor Aboud Rogo Mohammed in a similar drive-by shooting in 2012. Mohammed’s killing also sparked riots in Mombasa. The youth blamed both murders on police. Although so far there is no credible evidence that the police were involved, al-Shabaab will no doubt exploit such incidents for propaganda purposes to radicalize and mobilize Muslims.

President Kenyatta pays tribute to his nephew his fiancee at their funeral service in Nairobi, Sept. 27, 2013. AP By all accounts, however, the effort to turn Kenyans against each other has backfired. Prominent Somali leaders in Kenya, Somalia, and elsewhere have condemned the attack in no uncertain terms. President Kenyatta called on Kenyans to remain calm and united in the face of the tragedy.

And indeed, Kenyans have come together in a spectacular show of unity and resilience. After the massacre, thousands of ordinary citizens traveled to hospitals and makeshift clinics and waited for hours to give blood. Others cooked and delivered hot meals to first responders. Tens of millions of dollars were raised for the victims’ families.

The international community has also responded handsomely to the tragedy. Soon after the raid, Prime Minister David Cameron of the United Kingdom offered the Kenyan government Britain’s support. U.S. president Barack Obama also called to express his support. Other world leaders, in Israel and the European Union, similarly reached out to Kenya. Britain’s metropolitan police, the International Criminal Police Organization (INTERPOL), and the U.S. Federal Bureau of Investigation have been deeply involved in forensic and cleanup operations.

The Need for a Resolute Response

Terrorism thrives on financial support, and therefore curtailing access to funding is a key approach to weakening the organization. However, the unintended consequences of depriving the organization of funding must also be monitored carefully.

In 2010, the UN Monitoring Group in Somalia estimated that al-Shabaab was earning over $50 million a year from smuggling and extortion at the port of Kismayo. The group lost this lucrative port last year when Kenyan troops led a successful offensive that expelled the militants. The loss of its major source of funding played no small part in the transformation of al-Shabaab from a local to a global terrorist organization. Such globalization serves in effect as a fundraising campaign designed to mobilize support from international jihadists who are interested in attacking western targets in the region.

In response, the international community must come together to ensure that al-Shabaab does not metastasize into an even greater global terrorist threat. It has already demonstrated its ability to recruit fighters from Europe and the United States. The potential danger is that these EU and U.S. passport holders will return to the region and use their training to attack soft targets.

The international community should work to deny the terrorists access to funding. Since much of the money comes from abroad, international research could uncover and block such financial transactions. Somali businessmen in Kenya, the United Kingdom, and the United States should be encouraged to participate in this process. Cutting the terrorists off from their donors would deal a crippling blow to their capacity to launch meaningful operations.

Kenyan soldiers serving with AMISOM man an artillery position at Kismayo Airport in southern Somalia, August 2013. AP Al-Shabaab has been weakened militarily and can be marginalized further. But it will take an international effort to curb the organization’s reach. The African Union Mission in Somalia (AMISOM) has successfully confronted and defeated al-Shabaab in Mogadishu, and has expelled militants from the port of Kismayo.

But AMISOM’s commander General Katumba Wamala has warned that his resources are overstretched and that he needs more troops to put pressure on al-Shabaab. The United States, United Kingdom, and other supporters of AMISOM should seriously consider General Wamala’s suggestion that the operation’s strength be increased from the current 17,000 troops. Currently, the operation also lacks basic resources such as helicopters, which are critical for the pacification of a vast and hostile territory. The United States could provide basic intelligence and logistical support to move AMISOM to the next level (although this strategy is not without its risks).

On the broader level, the international community should work with moderates in Somalia and abroad to rebuild the Somali state. This does not mean a centralized parliamentary democracy such as those that exist in Europe. The people of Somalia are diverse and famously independent within their tribal (or clan) units. A federation of independent and semi-independent states could work well. The already-existing semi-independent states of Somaliland and Puntland could provide a blueprint for a future federation of Somali states. It is notable that Somaliland, for example, remained relatively stable for two decades while things have fallen apart in the rest of Somalia. At the same time, however, steps must be taken to ensure that the larger clans do not dominate the process at the expense of minority groups. Any settlement must ensure equal treatment for minorities such as the Zigwa people (the so-called Somali Bantu) who continue to face racial discrimination and dispossession in southern Somalia.

Finally, it is imperative that Kenya take pains to integrate Muslims, including Somalis, into its general population. The terrorists will continue to find fertile ground for radicalization so long as Muslims in Kenya are estranged from the broader nation. Efforts such as President Uhuru Kenyatta’s recent distribution of title deeds to so-called squatters at the coast are commendable. These reforms were due 50 years ago. Kenya’s allies can participate by supporting development projects (for such things as electricity and water) to depressed areas in the northeastern and coastal provinces.

Only through a multi-pronged strategy including security, development, and financial controls can the terrorist menace be managed.

The vicious attack on the Westgate Mall is a challenge that Kenya and its allies must meet without hesitation. But it is also a challenge that must be met without falling into the trap of indicting all Muslims for the atrocity. That would only serve the interests of the terrorists, whose ultimate goal is to radicalize Muslims in Kenya, and perhaps the world.