Conservatives are conservative, not libertarians, libertarians are part of the radical left, but who agree with conservatives on economic issues.
Libertarianism is a modern alternative to the democrat party, and typical, routine liberalism, yet while still leading the fight against conservatism with a fresh new approach that fits the times. It gives the chance for some liberals to leave the democrats and take over the right from within.
Russell Kirk on libertarians circa 1981:
http://www.mmisi.org/ma/25_04/kirk.pdf
“The ruinous failing of the ideologues who call themselves libertarians is their fanatic attachment to a single solitary principle- that is, to the notion of personal freedom as the whole end of the civil social order, and indeed of human existence. The libertarians are oldfangled folk, in the sense that they live by abstractions of the 19th century. They carry to absurdity the doctrines of John Stuart Mill (before Mill’s wife converted him to socialism, that is)...”