[Assassination using drone aircraft was perfected by the Israelis in cooperation with the U.S. The experimental population used are the Palestinians, used to test out a whole variety of anti-insurgency warfare techniques as well as population surveillance and control.]
Pilotless "drone" aircraft deliver a silent, deadly payload that has proved effective in killing militants, but has also killed civilians when intelligence goes awry or in "collateral damage" from a successful strike.
In Pakistan, strikes were infrequent - every few months - until August, when there was a sudden and dramatic increase in the drone attacks. Since then there have been at least 20 strikes - more than one a week - possibly in a stepped-up attempt to kill Osama bin Laden before George Bush leaves office on January 20 next year.
The intensity of the bombardment now has made the drone attacks a highly emotive political issue in Pakistan, feeding anti-Americanism. Pakistan's government and army protest loudly after each strike. And yet it is thought that Islamabad is secretly cooperating with the attacks, providing much of the human intelligence that allows the drones to target safe houses in the tribal area where al-Qaida militants are suspected of hiding out. The country even goes as far as hosting CIA agents in Pakistani army compounds in the tribal area, who call in the strikes.
Drones are operated by pilots who sit thousands of miles away, manning their controls from Creech Air Force Base in Nevada, in the US. The drones send back video images of the area they are flying over, which, together with human intelligence from agents on the ground, allow the pilots to pick out their targets. The Predator drones used by the US are each armed with two Hellfire missiles but are used mostly to spy on activity on the ground.
The drones that hover over the tribal belt are usually operated not by the US military but by the CIA, giving American generals plausible deniability that they are behind the strikes. Such is the perceived success of the clandestine drone programme that there is now a rush to train hundreds more US Air Force pilots to fly the remote-control planes.
Drones were originally deployed in Afghanistan before 9/11, as part of a then secret operation to get Osama bin Laden, and it seems they twice had him in their sights. But it is in Pakistan that the drones have become most notorious, as a seemingly constant presence flying high over the country's wild tribal belt, known as a haven of al-Qaida and Taliban militants. Terrified tribesmen regularly try to shoot them down but the planes fly too high.
The current campaign can be dated back to 2006, when on two separate occasions the drones targeted a village in the Bajaur part of the tribal area, on intelligence that al-Qaida number two Ayman al-Zawahiri was present. But it is thought that they managed to kill dozens of civilians instead, fuelling the tribal uprising against both the Pakistani army and international forces in neighbouring Afghanistan.
The drones have hit major al-Qaida operatives in the tribal area, especially this year, which has seen them kill Abu Laith al-Libi, a charismatic senior military commander, and Abu Khabab al-Masri, the terror group's chemical and biological weapons expert.