With these European elections coming up, I'm sorry that there is no mainstream Libertarian party to vote for. Sometimes I feel it could be successful, since the electorate often call for an alternative. They generally see no difference in policy between the major parties.
I believe that if there ever were a Libertarian party in Britain then to a good degree its success would depend upon how its marketed. If its representatives stated that 'taxation was theft', then I doubt it would get far. Yes, this is a libertarian belief, nonetheless the average Joe in Britain would consider that a 'far out', even extreme view. The key would be to state how the electorate would be better off without an income tax and with most current government services in private hands.
Similarly, if representatives of the party simply said that all narcotics should be legal then it would do little good. It would be more feasible to state how the War on Drugs is a failure and how society would be better with legalising narcotics.
One thing which has prevented the foundation of a libertarian party is the claim that the actions of certain libertarian think tanks/pressure groups (such as the Libertarian Alliance) would be comprimised. I don't fully understand this view, since in the United States there are libertarian pressure groups and think tanks in addition to a libertarian political party. In the UK, we have green/environmentalist pressure groups and a Green political party.
Several other liberal democracies have libertarian parties. Evidently the US has one, as does New Zealand and Australia. Why should the UK be any different?