Brief background on ash-Shabaab:
Al-Qaeda has always been active in east Africa dating all the way back to the early 1990's. Sayf al-Adel, a top military commander for al-Qaeda and a suspect in the 1998 US Embassy bombings in Kenya and Tanzania, was active in Somalia as early as February of 1993 and established a training camp on the Kenyan border. It is thought that some of his graduates took part in bloody Battle of Mogadishu (1993)--better known as "Black Hawk Down".
Another top al-Qaeda commander, Fazul Muhammad, another suspect in the 1998 US Embassy bombings, also took part in the battle. Fazul would later be named the leader of al-Qaeda East Africa (AQEA), as well as the military commander of ash-Shabaab before his death in 2011. Even further, Usama bin Laden (UBL) officially took refuge in Sudan after his exile from Saudi Arabia in 1992 (read: "Understanding Terror Networks" by Marc Sageman).
The group ash-Shabaab, however, traces its origins back to a group called the Islamic Courts Union (ICU) and an earlier group by the name of al-Itihaad al-Islamiyya (AIAI). AIAI was a radical jihadist group operating in Somalia, that received funds from wealthy Saudi's (including one Usama bin Laden). AIAI also reportedly helped AQEA launch the coordinated suicide attacks on the two embassies; something that landed them on the UN's list of al-Qaeda associated individuals and entities in the wake of 9/11.
The leader of AIAI, Hassan Dahir Aweys, would later go on to found the Islamic Courts Union. The ICU officially took over Mogadishu and large swaths of ground in southern Somalia in 2006. The Transitional Federal Government (TFG), a makeshift government set up in Mogadishu by Western powers, along with Ethiopian troops as a part of AMISOM effectively ran the ICU out of all their major strongholds and the ICU was disbanded.
Their militant-wing ash-Shabaab however, remained committed to the fight. Starting in 2009 when Ethiopia withdrew, Shabaab quickly began to retake lost ground. Clicking here will show you how much ground Shabaab took back after their offensive on the TFG began in 2009 and almost a year later (on the right). Fortunately, this tide has since been turning with Shabaab losing more ground to the US-backed AMISOM mission, including their main financial hub Kismayo.
While al-Qaeda had long since praised and published propaganda pieces on the ICU, Shabaab officially joined al-Qaeda in 2012. The link also provides a slew of names of top al-Shabaab/AQEA operatives, which provides an excellent insight into the groups connections and prowess--it should also be noted that there are several American members of Shabaab. Some of the leaders have since been killed, but I don't think that takes away from their potency. I also want to take the time (this could go on and on for a few posts) to point out that Shabaab also has at least one state supporter: Eritrea.
Local to Transnational:
Like mentioned above, the notion that Shabaab is just a local group should be long since gone by now. It should have been gone in 2010, when they killed seventy-four people in Uganda, but I digress.
Since a renewed US-backed AMISOM mission started in 2012, Shabaab has threatened retaliatory attacks across the Horn of Africa. Besides the aforementioned attacks in Kenya, Shabaab has also been responsible for attacks in Djibouti. Djibouti, a tiny country neighboring Somalia to the north, also hosts the only US military base in the region. As a result, Shabaab has threatened more attacks there. Not only that, but they have threatened to conduct more attacks in Kenya, Uganda and even the United States; the latter of which sometimes directly intervenes.
But let's also look at Shabaab's connections to other al-Qaeda groups.
Shabaab is known to financially support Boko Haram. They have a "terror partnership" with al-Qaeda in the Arabian Peninsula (AQAP). Shabaab is also said to be "synchronizing their actions with Boko Haram and al-Qaeda in the Islamic Maghreb (AQIM)". No matter how you look at it, Shabaab is a well-connected group and appears to be advancing al-Qaeda's goal of the global jihad.
Looking specifically at the "terror partnership" with AQAP, this could be a dangerous scenario if both of these groups begin to seriously work together to target the United States. A "terror partnership" between the two should also come as no surprise. With close proximity and knowing al-Qaeda branches share resources and fighters, it only makes sense. Pooling their resources together, they would be able to effectively use AQAP's bomb making methods and Shabaab's excellent recruiting methods in the United States to conduct terrorist attacks here.
By "synchronizing their actions with Boko Haram and AQIM", Shabaab could extend their reach from the Horn of Africa to the heart of Nigeria and even into Mali and Algeria. All three could pool their resources together and effectively threaten US interests in a large portion of Africa.
What can the United States do?
The United States can continue to work with regional partners in the area to combat the threat of Shabaab and to mitigate the relationships between Shabaab and various other al-Qaeda affiliates and branches. Working with African troops to build up their capabilities, assisting them in battle with intelligence support and even aerial support, as well as conducting military raids and drone strikes when needed. The United States also need to be investing in the political, social and economical factors of terrorism; working with the regional governments to clamp down on recruitment efforts, to help their economies grow, to work with political and social leaders, and to encourage religious leaders to speak out against Shabaab. The United States will also need to work to influence state actors, like Eritrea, to stop funding Shabaab and/or discouraging their citizens from doing so as well.
The threat emanating from Somalia extends beyond the region of the Horn of Africa; It is expanding across Africa and even into the Arabian Peninsula. One day, it could even begin to stretch westward. We should be trying to stymie their aspirations of attacking us.
Note: It is usually seen as "al-Shabaab", but as a student of Arabic I prefer the correct way of transliteration. In Arabic there are essentially "sun" and "moon" letters. "Sun" letters absorb the lam (the l in al) into the initial sound of the following noun. So, shiin (the "sh" sound) is a "sun" letter. Knowing this, it should be "ash-Shabaab". There's your Arabic lesson for today.