Britain has allowed the American CIA (Central Intelligence Agency) to recruit and run its own informant network among Britain's large Moslem community. This is because Islamic terrorist organizations have, for years, been aggressively recruiting among Moslem populations in Europe, especially in Britain. It's hard to get numbers, but the effort has had some success. At least a dozen British Moslems are known to have died in Iraq, while serving the terrorist cause. At least three of them died as suicide bombers. Over fifty are believed to have gone to Iraq, and over a hundred, over the last seven years, have gone off to be active terrorists around the world. That's about twenty people per million British Moslems per year. Most of those are actually not British, but men born in the Middle East or Pakistan, who sought political asylum in Britain. Many of these men were found to have had a terrorist background, and had fled from their native countries, and sought refuge in Europe. Until recently, most European countries, and particularly Britain, were quick to grant asylum to these terrorists. While most of the terrorist "refugees" simply lied about their backgrounds, some admitted to their disagreements with their home governments, and got asylum anyway, or simply refused to show up when the immigration authorities called them in to explain exactly what they were fleeing from. Although many Europeans still back easy asylum policies, the trend is towards taking a closer look at those trying to get in. When this is done, it is often found that many of the refugees are basically criminals or terrorists looking for a place to hide out.
In Britain the big problem is that there is a tremendous anti-Western attitude in the British Moslem community. For that reason, there are fewer than 400 Moslems in the British armed forces, and efforts to increase that much have, so far, been futile. Since large numbers of Moslems (mainly from Pakistan and India) began arriving in Britain sixty years ago, there has been a lot of discrimination. The recruiting difficulties are one of the side effects. Interestingly, the French military is over ten percent Moslem, mainly because the unemployment rate of Moslems is much higher in France, and the military will take anyone who is French, physically fit, and without a criminal record. But the French are a bit nervous about how much they can trust many of the Moslem soldiers. So far, there have been no problems. However, a British Moslem soldier was arrested and convicted of spying for Iran while serving as an interpreter for the senior British commander in Afghanistan.
The U.S. has not had such problems with recruiting Moslems. The reason is that the culture in the United States is geared toward eventually accepting immigrants. Most other nations, which are not composed largely of immigrants, or the descendents of immigrants, are generally much more hostile to "others." For this reason, some of the CIA operatives are from families that immigrated from South Asia to the United States. These agents, even if they don't speak South Asian languages well (or speak the right ones), have an easier time connecting with British Moslems (who know of the easier time Moslems have in the United States.)
This novel arrangement annoys some CIA officials, who believe the British should take care of their own Moslem problem. But U.S. and British intelligence officials are practical, and recognize that you go where the most opportunities are. Britain has most of the South Asian (particularly Pakistani) migrants in Europe, and this group is the most likely to have, or develop, contacts with Taliban and al Qaeda groups in Pakistan. So the CIA, MI-5 (British domestic intelligence) and MI-6 (British foreign intelligence) coordinate their efforts, and pool information to spot, and block, terrorist operations in Britain. Meanwhile, the CIA also collects information on terror operations outside Britain, that are being planned or supported by Islamic terrorists inside Britain.