Whether you think they are good in themselves or not, there are some events which become teaching moments. Rand Paul's candidacy is surely one of them. His candidacy is an opportunity to make a clearer distinction between libertarianism and traditional conservatism.
I have said before that libertarianism is conservatism without a soul. But this definition is a little too general (and certainly too cheeky) to be useful. Here is, I think, the central problem with libertarianism and what makes it different than traditional conservatism: libertarianism sees freedom as an end rather than a means.
For the libertarian, any restriction on freedom is, by nature a bad thing. This is why someone like Paul gets in trouble when sharing his thoughts on civil rights laws. Civil rights laws impinge on the freedom of business owners, no question about it. And if this is you're only criterion for judging the justice of a law, then this is how it will look to you.
However, if freedom is only a means, rather than an end, then you are not driven inevitably to this conclusion. To the traditionalist conservative, freedom is not an end, it is a means--a means to the end of the common good. Furthermore, it is only one of several means toward that end. If this is true, therefore, the worth of civil rights laws cannot solely be decided on the criterion of whether they interfere with the freedom of private business owners, but whether the benefits they have toward the common good outweigh the interference with that freedom. The libertarian's philosophy disallows him from even asking this question, since it introduces a criterion he doesn't even recognize.
This is the whole problem with the Tea Party Movement--and any other neoconservative movement: it doesn't recognize or understand the distinction between freedom as a means and freedom as an end.
The position of his critics, mostly liberals, however, is hardly any better. They have even less justification for supporting civil rights laws. If we are to take their criticism of abortion laws as an example--that they "impose morality"--then how can they justify the support of civil rights laws, which clearly impose morality? But there is much more to be said on this that I don't have time to say here.