Kenya has long been uneasy about the activities of radical Islamist al-Shabab fighters across its borders. The straw that broke the camel's back, from Nairobi's perspective, came last Thursday, when al-Shabab allegedly kidnapped two Spanish women working for the humanitarian organization Doctors Without Borders in the Dadaab refugee camp.

An al-Shabab spokesman denied involvement, but the Kenyan government wasn't convinced and sent in troops. Kenyan forces have advanced more than 100 kilometers (62 miles) deep into Somalia to hunt down Islamist insurgents and create what experts describe as a "buffer zone."

"If we are attacked by the enemy, we have the right to pursue that enemy," Kenyan Defense Minister Mohammed Yusuf Haji told a news conference on Monday, in justifying the military mission. "(Al-Shabab) have abducted so many people, they have fired at the military, they have blown up military vehicles with mines, and it's getting to be too much. Therefore we have decided as a country that we cannot sit and watch the situation escalating."

Speaking at a press conference at a secret location near Mogadishu, al-Shabab spokesman Ali Mohammed Rage demanded that Kenyan troops withdraw from Somalian territory.

"If they fail to withdraw, we shall fight them and drive them back to their country," he said.

But Kenyan Foreign Affairs Minister Moses Wetangula, who is currently holding talks with authorities in Mogadishu, said al-Shabab has no capacity to fight with Kenya in an open-ended conflict.

"Let them try," he said. "Kenya has the capacity, the ability, the will to defend its territory, its people. The consequences will be dire to anybody who thinks that they can now walk in and out of Kenya to lay mischief with impunity."

Cross-border jihad

Al-Shabab, whose name literally means "The Youth," coalesced in 2006 with the express aim of overthrowing the Somali Transitional Federal Government (TFG) and establishing an Islamist state and Sharia law in Somalia. In the past two years, the group has succeeded in bringing significant stretches of southern Somalia, along the Kenyan border, under its control.

Al-Shabab long denied it had connections to al Qaeda, but in 2010 leaders did confirm they were working in an international framework with the world's most notorious terrorist group.

The insurgents' animosity toward the Kenyan government stems from their belief that Nairobi is actively allied with the TFG in Somalia's civil war. Kenya denies this.

"Kenya has lived in a harmonious way with Somalia on the border," Haji said. "If and when we were asked to contribute soldiers, we declined to do so because we though that Kenya, being an immediate neighbor, should not be engaged in any security affairs of Somalia."

But in February 2010, al-Shabab declared jihad on Kenya, saying the Kenyan army, in conjunction with TFG, was preparing to attack southern Somalia.

The TFG would be more than happy to see Kenyan troops wipe out the insurgents, but not at the cost of control over its territory. Thus, a rather bizarre situation has emerged: Somalia's envoy to the United Nations has protested against the Kenyan military operation while Somali government troops have reportedly been taking action of their own, coordinated with the Kenyans, against al-Shabab further to the north.

And that's not the only complicated constellation of interests involved in this conflict.

Foreign visitors

Kenya's decision to pursue a military solution against al-Shabab is based on concerns that go beyond security in a narrow sense.

"Kenya is particularly now becoming more robust because the actions of the group are having a massive impact on the tourist industry," Atta Asamoah from the Institute for Security Studies in Nairobi told Deutsche Welle. "Remember that Kenya depends a lot on tourism. Kenya cannot afford to be seen as a weak link that is not in control of its territorial integrity to the extent that tourists do not have the security they need to enjoy their presence in the country."

Tourism is the biggest industry in Kenya and represents an overwhelming part of the service sector, which accounts for 63 percent of the country's GDP. So Kenyans are very mindful of anything that might scare off foreign visitors.

The industry has just fully recovered from a decline in tourism after the political unrest in 2007-8. So that's one reason the government is taking a no-tolerance approach to al-Shabab.

Yet the question remains whether direct military action will help or hurt the general security situation.

An asymmetrical battle

The Kenyan government is unlikely to encounter much international resistance to their pursuit of al-Shabab, especially as the terrorist group is one factor worsening the drought crisis that has left as many as 11 million people threatened with starvation.

But al-Shabab, Asamoah points out, is by no means an easy adversary, as their success within Somalia shows. The border between Kenya and Somalia is huge, making it difficult to police.

Moreover, al-Shahab is able to recruit foreign fighters, and Kenyan forces will be confronted with all the problems typical of asymmetrical warfare, including potential terrorist attacks at home.

"The risk is that the group begins to activate sleepers within Kenya and operate within Kenyan territory," Asamoah said. "This is going to be a dangerous time."

Predictably, al-Shabab has already vowed to launch terrorist attacks within Kenya, and police there are issuing warnings.

"I appeal to Nairobians and Kenyans in general to be extra alert, and in case anybody sights any suspicious and strange person or any suspicious object," Nairobi Provincial Police commander Antony Kibuchi said on Tuesday.

But along with that vigilance comes the threat of persecution or reprisals against ethnic Somalis in Kenya, according to Patrick Smith, Africa specialist at the London-based newsletter Africa Confidential.

"(Kenyan Somalis) will feel rather vulnerable because they will be associated with the al-Shabab," he said. "That could cause internal problems within Kenya."

Author: Amine Bendrif/Jefferson Chase
Editor: Rob Mudge