UK Head of MI5 warns that 2012 London Olympics face growing terror threats

The biggest threats no longer come from Pakistan (thanks to US drones killing al-Qaeda leaders) but rather from Yemen and Somalia, where British nationals are being trained by al-Shabaab terror groups.

I guess nobody thought of restricting entry to the UK by Muslims from those countries, especially British Nationals, unless the purpose of their trip there can be verified. Limiting immigration from all Muslim countries would be even better. But what do I know?