I've just finished Andrew Rawnsley's `The End of the Party <http://www.amazon.co.uk/End-Party-Andrew-Rawnsley/dp/0670918512>`__ and in the period when Brown thought a Lib-Lab coalition was a possibility there's this brief anecdote:
'He felt his legacy could be a progressive coalition. Brown imagined a final six months at Number 10 as the sort of benign, presidential 'father of the nation' figure he had often dreamed of being. Talking to Tom Fletcher that evening, Brown said: "If we somehow pull this off, you'll find I'll turn into President Bartlet.'"
That Brown with his long-standing affinity for America would reach for The West Wing as a model for a national leader perhaps isn't that surprising but the infulence of the show is a recurring presence in British politics, from rumours that George Osbourne was basing a No. 10 floor plan around the West Wing to a'West Wing plot' leading to a government defeat and, more recently, Ed Miliband's advisors ending meetings declaring 'Let Bartlet be Bartlet'. Biblical allusions might now past us by, but everyone knows who Josh is.
Tom Harris takes the lack of a British West Wing with an optimistic and positive portrayal of politicians partly as a failure of the nation's appetite (which he sees as being incapable of digesting a show that earnest if the accents were closer to home), but also the nation's writers - unable to write politicians as anything other than cynical or corrupt. I think this oversells the case, British television may not have produced the West Wing but American television only barely did, producing it just once and common portrayals of politicians in the US often skew closer to the cynical. Not to say there's nothing to the idea of national tastes but I think that there are specific structural problems with crafting a positive show about the machinery of government that make it easier to achieve in the US than the UK. A clue as to why is Abigail Nussbaum's take that the West Wing is essentially a show about the royal court of a more politically acceptable medieval monarchy. Interestingly she points out one of the most obvious example of this interpretation is from the same episode that Miliband's advisors are drawing from, "Let Bartlet be Bartlet":
Leo turns to each of the staff as they recite "I serve at the pleasure of the President of the United States." He isn't leading a pep rally; he's reminding them of their oaths of fealty, and reminding Bartlet, who is standing just outside the room, of the courage and devotion of the men and women he commands.
Put in this context it's quite clear why something with the tone of the West Wing would be quite hard to achieve in the UK - while the US political system sanitised the trappings of monarchy, the UK instead moved power into different arenas. The characters in the West Wing are all attempting to implement the agenda of one man while also trying to shape that agenda - the show's universe revolves around the President and his staff's loyalty to him. While the British Prime Minister is potentially more powerful, they are not the only one in the room who matters, their power base is only one among many. In the Parliamentary system many of the key positions of government are staffed by MPs with their own electoral mandate and their own overlapping and shared (but also unique) agendas. Prime Ministers live with the constant knowledge that the party as much as the electorate will be the eventual decider of their fate. If a British Bartlet had concealed their MS, their decision to seek a second term would be likely to be far less of a personal decision.
Conflict is the bread and butter of drama and while the check-and-balance heavy US system is filled with potential external opponents for the team (it's not a coincidence that there's a Republican Congress for the entire run) meaning that while there are conflicts within the team, they remain low key and amicable. For a UK government with a majority there are few effectual external opponents - the primary antagonisms are then within the party, within the government and within the main cast. The West Wing transplanted to the New Labour era would have the PM with the ability to do pretty much anything he wanted, unless it was blocked by the second-billed character, a long-term friend turned antagonist. Bartlet's troubled relationship with his Vice President is ultimately harmless because the Vice Presidency isn't necessarily powerful (it's not a surprise that Iannucci's US version of The Thick Of It is based around the VP), the nearest analogy would be if Bartlet and Leo were at each other's throats - it would be very hard for for the West Wing to be an optimistic show in this context.
Because the institution of the Prime Minster is relatively flexible, depending on the circumstances of their election and the style of the leader (the Major era very different from Blair, very different to Cameron, etc) there's no equivalent to the status of the Presidency (except, of course, the Monarchy). The positive feelings and glorification of the institution's history as well as the status-quo bias of the US policy process justifies a kind of mythic stasis - big projects of the staff like Sam's Manhattan project for beating cancer, Josh and Toby's tax-deductible tuition are ultimately stories about why these things didn't happen. There are battles, some of which are won and some of which aren't, but the status quo of the West Wing mostly remains the same - there have always been kings and knights on horses defending the realm and there always will be, they will be fighting about gun control, gay rights, religion in government, today and tomorrow, and tomorrow and tomorrow. That the characters take sides in this eternal conflict without scoring any lasting successes (this only really applies to the Sorkin era, once he leaves they quickly bring peace to the Middle East) is arguably realistic in the context of a political system where paralysis is envisioned as a positive feature and so even failure can glorify the system. The ability of a British government to achieve change (and the expectation that they will which stigmatizes failure) combined with a lack of a long-term, static institution of the Prime Minister would make it difficult for a British West Wing to find the same amicable atmosphere where characters sit around and talk about timeless issues in a consequence-free way.
While none of this completely rules out the possibility of a optimistic and earnest show about British politics (I've been trying to get hold of the 'Number 10' Radio 4 plays to see if they pull it off), it does make it easier to understand why The West Wing has only happened once in the US and not at all in the UK. The 'royal court' take on the West Wing would actually suggest we've had several films in the previous decade that had optimistic and positive portrayals of the British system, they were just all about the monarchy.