Well duh, the only reason Murray is included in this group is because he's from the UK. If Murray was from Iran or Russia he would NEVER be included in this group. Don't try to act as though nationalism and western imperalism has nothing to do with this. The western world especially the English speaking western world just can't stand it that one of their own isn't as good but they have to squeeze Murray in their even though he's the worst out of the top 4. Murray doesn't deserve to mentioned in the same sentence as Federer, Nadal, and Djokovic isn't fair to them to be compared to player that crumbles in slam finals.
Well, he's one of four players on tour who can consistently make major finals and win Masters events. I think you're getting upset at nothing here. I have no doubt in my mind that if a player from Iran had Murray's exact resume, he would still be considered part of the top four. People still talk of the Big Three when they want to distinguish Murray from the all-time greats, but at the same time there is a very clear big four that is far superior to all of the players ranked below them (and Ferrer, who is lucky to be above Nadal at the moment anyway).