It's interesting most responses here have been from the legal side, I.e. protestors not sentenced strongly enough, but ignoring the legal point that they were making. Now I don't necessarily agree with their point but there is a certainly a case to debate.
US drones, if not ours, are killing people on a daily basis in Pakistan although, they aren't at war. Would you walk up to someone, terror suspect or not, and shoot them in the head with no legal process and expect that to be the end of it? Why is it different if a drone rather than a pistol is used? How would we feel if the Pakistan Air Force was killing people this way in the UK.?