Nairobi terror attack has brought the direct threat long posed by al-Shabaab into focus

In many ways, the conflict in Somalia between the internationally supported government and the al-Qaeda linked militant group al-Shabaab, can be described as one of the most important international issues affecting the UK, which is also the least talked about, or reported.

It has taken a horrific massacre in Nairobi to bring this conflict to light. Suddenly, we are slowing waking up to how what is happening in Somalia affects us directly.

It's an issue that David Cameron is personally committed to. He has convened two international conference for Somalis in the past two years which were held in London and attended by senior government officials from the USA, Turkey, the Arab League and the European Union.

The UK has no assumed the lead position in the international community's response to Somalia; from the the number of intelligence and counter-terrorism officials who travel in and out of the capital Mogadishu, to the building of a new embassy in the Somali capital, and in terms of the financial support for the rebuilding of the Somali army and security forces.

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The first reason the UK has taken this stance is because of the number of British citizens who have travelled to Somalia in order to fight for al-Shabaab. Given the the nature of al-Shabbab, the hidden ways in which young British Somalis and young British Muslims are radicalised and recruited, it is hard to come any hard and fast numbers.

The British security services and the Metropolitan Police are loathe to go public on putting a number on such British jihadis joining al-Shabaab but they estimate that the number is likely to be between 50 and 100.

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The elected Somali government, which has already been battling the group across the country for over 6 years, broadly agrees with the figure, but says it could easily be higher. The obvious fear of course is that these young British fighters could return to the UK, having been trained in bomb making, kidnapping and other terror tactics and carry out spectacular attacks on the UK mainland.

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One thing that makes it harder to know the exact scale of British fighters with al-Shabaab is that so many of the young me and presumably young woman make their journeys to Somalia without telling their family. In fact the only time their relatives hear that they have gone to join the group is when the receive a phone call from Somalia from the fighters once they are there, informing family members they have gone to fight against "unbelievers and crusader armies" who they say are "occupying" Somalia.

I know of many Somalia families who have no taken to hiding the passports of young men they are worried are being radicalised in order to stop them making this journey.

The other key factor in preventing Somali families coming forward and seeking help is that there is a widespread belief within the community that they face intrusive and often unsympathetic attention from the British security agencies.

The recruits serve three main purposes for al-Shabaab, who have recruits from many other western countries, especially the United States, Canada and Scandanavian countries. First, they are used for suicide missions.

Often these recruits arrive in Somalia without any understanding how much of a 'fish out water' they will be. They have no local contacts, sometimes don’t speak the Somali language, and have no clan or tribal connections that could help them.

They are therefore more vulnerable to indoctrination for suicide missions. In fact al-Shabaab has a separate brigade forsuch British and other foreign recruits – known as the 'Muhajiroon' brigadewhich means “those who have migrated from abroad”. Local Somali fighters of Al Shabaab are better trained, have more skill as fighters so are less likely to volunteer for such missions.

Secondly, these foreign fighters are used to make recruitment videos, where they urge other young Britons to join them. The videos are then distributed on the internet.

The sight of another young British Somali or British Muslim, speaking their own language, can often be a powerful tool of persuading radicalised young men to take the same path.

Thirdly, these recruits are an important tool of self-financing for al-Shabaab. Quite often, when the fighters arrive to Somalia it is not as they imagined it. A number find the conditions and hardships much harder to bear and some become disillusioned.

The fighters are not allowed to leave the organisation. They then face a choice. They can’t be forced to carry out a suicide mission in case they fail to go through with it and give themselves up to government forces. But instead of executing them, al -Shabaab decides to make money out of them.

They contact the families of the fighters in the UK or Europe or the US and say that they will be allowed to leave if they pay a ransom. I met one such family who’d done exactly that.

They live in West London and when they got the call from Mogadishu they were relieved that their son, Ahmed, was still alive. They agreed to pay the ransom. They refused to tell me how much it was but it was in the tens of thousands of pounds.

However Ahmed is still stuck in limbo, living with extended family in Somalia, because the family is terrified that he will be picked up by the British security forces and interrogated.

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