In October 2011, Kenyan forces invaded southern Somalia with the stated purpose of dismantling al-Shabaab. The forces are part of the African Union Mission in Somalia.
Kenya signed a Memorandum of Understanding with the African Union in June. U.N. Security Council Resolution 2036 four months earlier authorized the expansion of AMISOM from 12,000 soldiers to just more than 17,700. Under AMISOM's policy, 5,000 Kenyan forces were reassigned to Sector 2, Middle and Lower Juba, to work alongside troops from Sierra Leone.
The Kismayo assault comes as Somali members of Parliament prepare to choose a new president under a U.N.-brokered peace plan in an election scheduled for Monday.
In August militant al-Shabaab Islamic insurgents lost control of Merca, Somalia's third biggest port city after Mogadishu and Kismayo, to AU and pro-Somali government forces.
With 2,050 miles of shoreline on the Indian Ocean, Somalia has the longest coastline in Africa, and analysts state that the capture of Kismayo will boost Somali government revenue and improve trade between Somalia and the rest of the world.
Two months ago Kenyan Prime Minister Raila Odinga appealed to the United States and European Union for fiscal assistance for a "final onslaught" by on Kismayo. Kenya first sent troops under AMISOM command in 2011, with Nairobi justifying the deployment by stating that it wanted al-Shabaab defeated because the militants threatened its Kenyan security.
Kismayo is al-Shabaab's last stronghold in Somalia after the fall of Marka and Afmadhow in the Juba area, The Star newspaper reported on Tuesday.
In 2011 al-Shabaab, which is affiliated to al-Qaida, withdrew from Mogadishu after heavy fighting with AMISOM and Somali government forces. As Kenyan AMISOM forces have moved through southern Somalia, al-Shabaab has mostly avoided engaging them in direct combat.
Kismayo may prove different however, as it is the center of al-Shabaab's finances. Al-Shabaab may prove unable to repel a direct assault however and analysts say that its guerrillas may continue to disperse to rural areas in southern Sudan or to other countries in the Horn of Africa.
There are worries that al-Shabaab may choose to use targeted killings in Kismayo if they believe that they are losing the city to terrorize the city's occupants from co-operating with AMISOM, especially as these types of retaliatory attacks have been increasing in the capital Mogadishu and accordingly AMISOM must be prepared to protect the civilian population if this tactic is employed in Kismayo.
The Kenyan Somali deployments have given the Kenyan contingent of AMISOM combat experience beyond previous perceptions of its being a relatively untested "career army" that might soon gain experience in urban guerrilla warfare should al-Shabaab decide to defend Kismayo. As a result of its AMISOM Somali deployments Kenya is becoming an important element in an increasingly successful, coordinated regional effort to address security problems, which ultimately may provide Somalia's Transitional Federal Government the political and economic space it needs to consolidate its progress in Somalia.
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