In the rapidly changing battleground against international terrorism, the arid plains of the Horn of Africa are becoming a steadily more significant base from which al-Qa'eda's followers can launch their attacks.

The Horn now ranks alongside the Middle East as the area of greatest concern to British counter-terrorism officials, coming second only to Pakistan, where al-Qa'eda's core leaders are ensconced.

Al-Qa'eda operatives based in the Horn, probably in the failed state of Somalia, could choose to target Britain, which has a large Somali community. Of the four men convicted for the failed bomb attacks in London on 21 July 2005, all were from the Horn and two were of Somali origin.