The two British men executed by US drone attacks in Pakistan were not killed in combat. They were assassinated while going about normal life. This is a most barbarous practice, which amounts not just to execution without trial, but to inaccurate execution killing many who were never accused in the first place.
Being British does not make these particular victims more important than the thousands of others – including numerous women and children – that the US has assassinated in this way. But it does give the British government a standing to protest. Sadly there is no chance that the neo-cons in power will do anything about it. If there was one area where you might have expected the Lib-Dem presence in government to give it a slightly more liberal tinge, it was foreign affairs. In fact, there has been no evidence of that whatsoever.