I am wary of making a specious correlation, but it has been my personal experience that the majority of designers, whether graphic, industrial, textile or architectural, tend to have views at least slightly to the left of the mainstream.
The first answer has to be the art college education. Art colleges are surely the most liberal institutions in the land today.
While universities and student unions struggle with the petty tyrannies of bureaucracies (of the left and right alike), art colleges are home to social anarchism: naked performance art, pornographic images and a heady mixture of strident individualism and collective solidarity.
But that can't be all there is too it. For a start, graphic design courses tend to be significantly more conservative (and work-centred) than fine art and architecture is rarely studied directly alongside fine art or visual communication.
A few years back, Irish architect and libertarian conservative blogger Frank McGahon, writing for the right wing web site Samizdata, came up with a rather different reason why designers in his particular discipline tend not to share his 'don't tread on me' political outlook:
Running your own business is a pretty good way of disabusing yourself of any lingering enthusiasm for state regulation and mandatory collective provision. That those in business tend to be capitalists is an obvious, platitudinous assertion but there remains one profession which is perversely immune to free-market reason and where public sector boosterism persists, my own: architecture.
A platitudinous assertion? Maybe, maybe not. An overly broad assertion, yes. Nevertheless, there is probably a kernel of truth in what McGahon says, even if the low-rent (cough) businessperson writing this blog hasn't yet joined the ranks of the plutocracy.
He goes on:
Leaving aside the obvious fact that architects in the public sector or benefitting significantly from public sector work tend to favour an expanded public sector, there are a number of factors which explain why architects in general are often prone to left-leaning politics: [...] Architects are romantics [...] Architects think in soft pencil [...] the cherished notion that architectural practice is a vocation [...] Architects are planners [...]
McGahon's last point is the most interesting of all.
Of course, design is fundamentally about problem solving and problem solving is not a traditional concern of those of a conservative bent. In the last century at least, the main political battle was over the issue of preserving continuity with the past versus constructing a better future.
I recently discussed this issue with a correspondent of mine. This is part of what he had to say:
I think this is the most interesting question, because most designers certainly seem to *feel* liberal, but they aren't, generally, as active as other groups of people. I consider most businessmen to be very active and able to converse in issues of politics (usually of the conservative leaning) - they follow the news, and are able to discuss and articulate how legal decisions affect them and their day to day jobs. Designers, on the other hand, hardly seem to be aware that the world around them is, in fact, spinning around and advancing (or regressing, as the perspective may seem). If they do poke their heads above ground to read CNN or the BBC, they seem stuck in a rut of complaining about how things aren't right, but very infrequently do we hear about designers doing things to change worldly issues. When they do, they are the type of unfortunate liberal suggestions you already mentioned in your online post that I referred to; benefit concerts, etc.
I think most designers associate more with being "liberal" because (in my opinion, of course) design exists to make the world a better place. This usually implies a sense of service, and while that service need not be altruistic, it usually involves helping people. I don't think there are that many practising designers left who design only because they "like to make cool stuff"; I think there are a larger group who design because it involves righting the wrong and solving problems.
I will return to this subject. With monotonous regularity.