Bin Laden was hiding out in a million-dollar compound with all the security in the world, but ultimately when his house-mate/courier Sheikh Abu Ahmed picked up the phone, the US military knew they had their man.

We learnt yesterday that the courier led officials to the compound, and that other signs—such as a lack of internet or phone line, and their overcautious burning of their trash—tipped them off to the compound's true resident. But how did they place the courier in the compound?

After being tipped off by one of the 9/11 detainees to the courier's relationship with Osama, the US searched for him for years, believing his name to be Abu Ahmed al-Kuwaiti. It wasn't until Ahmed spoke on the phone some distance away from the compound to someone being tapped from the US, that they knew they had the rough area for bin Laden's lair.

Despite only storming the compound on the 1st of May, US military actually tracked Ahmed to the compound last August—nine months ago. We know that in this time they were planning their attack, and even built a replica version of the compound to practise their entry.

Ahmed the courier, his brother, and bin Laden may be dead now, but if Ahmed ever knew it was just one single phone call that led to their downfall, I bet he'd rue the day he ever picked up that handset. [SFGate]