Hardly any one who claims themselves to be a libertarian considers libertarianism a fascist ideology...
A lot of us on the libertarian left do.
"Libertarianism is Fascism
1.
The Cult of the Superior Man. Both libertarians and fascists think the world is divided into superior and inferior people, ubermenschen and untermenschen, and they both believe that most of the evil in the world comes from inferior people keeping the superior ones down. They both promise to release the best and the brightest from the shackles placed on them by the unworthy - whether the unworthy happen to be the "lazy poor" or "government bureaucrats" or "dirty Jews" or immigrants.
The only difference between libertarians and fascists is that libertarians don't believe (or they say they don't believe) that superior people should enforce their will on inferior people. But this is a thin line, easily crossed. Once you've convinced yourself that you're better than everyone else, it's easy to justify repressing the ignorant masses, for their own good. Which leads us neatly to the second point...
"It would be absurd to appraise a man's worth by the race to which he belongs and at the same time to make war against the Marxist principle, that all men are equal, without being determined to pursue our own principle to its ultimate consequences. If we admit the significance of blood, that is to say, if we recognize the race as the fundamental element on which all life is based, we shall have to apply to the individual the logical consequences of this principle. In general I must estimate the worth of nations differently, on the basis of the different races from which they spring, and I must also differentiate in estimating the worth of the individual within his own race. The principle, that one people is not the same as another, applies also to the individual members of a national community. No one brain, for instance, is equal to another; because the constituent elements belonging to the same blood vary in a thousand subtle details, though they are fundamentally of the same quality."
-- Adolf Hitler, "Mein Kampf", volume II, chapter 4.
"Fascism.. asserts the irremediable and fertile and beneficent inequality of men."
-- The Doctrine of Fascism, authored by Giovanni Gentile, signed by Benito Mussolini
2.
Opposition to democracy. Both libertarians and fascists hate democracy because they don't think inferior people should be able to tell superior people what to do. They both hate democracy because democracy gives power to the "unwashed masses" on the assumption that all people are equal. It's important to note, however, that libertarians and fascists are not necessarily hostile to the masses themselves - in fact they are often populist, from Mussolini to Ron Paul. They are only hostile to the idea of equality among the masses, and most of all to the idea of equality between the masses and the elite. Libertarians and fascists often genuinely believe that they are working to help the people, the masses, but they believe that salvation can only come from above, from the elite. Which leads us to the third point...
"Mankind is not a uniform and equal mass. There are differences between races. The Earth has received its culture from elite peoples; what we see today is ultimately the result of the activity and the achievements of the Aryans. Decisive within each race, however, are the personalities it is able to produce. Personalities have created the cultural shape of mankind and not democratic majorities."
-- Adolf Hitler, quoted in "The rise of the Nazis", Conan Fischer. Manchester University Press: New York, 1995. Page 139.
3.
Belief in Natural Hierarchy. Libertarians and fascists are elitists, and moreover they believe that elitism and hierarchy are part of the natural order of things. The phrase "rebellion against nature" has been used by libertarians and fascists to describe the political views of their enemies - particularly egalitarian views. Libertarians and fascists don't think their kind of society is the best among a number of competing kinds of viable societies, they believe their kind of society is the ONLY viable, "natural" kind of society. Libertarians and fascists tell the masses that they have to subject themselves to hierarchy for their own good, because hierarchy and inequality is the only way to have a civilized society.
"There are three ways of settling the social question: The privileged class rules the people. The insurgent proletariat exterminates the possessing class. Or else our third formula that gives each man the opportunity to develop himself according to his talents."
-- Adolf Hitler, quoted in "Hitler's Secret Conversations", translated by Norman Cameron and R.H. Stevens. Farrar, Straus and Young: United States, 1953. Page 267.
Those are the fundamental similarities between libertarian and fascist thinking, but there are also many other, less vital parallels:
4.
Belief that the unfortunate get what they deserve. If hierarchy is natural, it follows that those at the bottom of the hierarchy are there through their own fault or their own flaws. Libertarians think the poor deserve to be poor. Fascists think oppressed races deserve to be oppressed. Both libertarians and fascists have voiced support for the "IQ and the Wealth of Nations" thesis - the idea that poor countries in Africa and Latin America are poor because their people are stupid.
"It is my firm conviction that property rights... must be unconditionally respected. Any tampering with them would eliminate one of the most vital incentives to human activity and would jeopardise future endeavour."
-- Adolf Hitler, quoted in "Hitler's Secret Conversations", translated by Norman Cameron and R.H. Stevens. Farrar, Straus and Young: United States, 1953. Page 368.
"The individual must be given more latitude and be taught to cultivate a sense of responsibility and a readiness to accept it."
-- Adolf Hitler, quoted in "Hitler's Secret Conversations", translated by Norman Cameron and R.H. Stevens. Farrar, Straus and Young: United States, 1953. Page 536.
It is true that fascists think poor nations are poor primarily for ethnic reasons. But not only for ethnic reasons. Fascists also always made the argument that certain nations - particularly Russia - are poor because of communism:
"Russia could be a land of plenty, but the production of real values is forthwith utterly destroyed by Bolshevism [...] and such production cannot be brought into working order again even after twenty years."
-- Adolf Hitler, quoted in "The Speeches of Adolf Hitler", translated by Norman H. Baynes. Oxford University Press: London, 1942. Page 705.
5.
Conspiracy theories. Unlike Marxists, who recognize that different social and economic institutions are appropriate at different stages of history, libertarians and fascists believe that their ideas are always valid, everywhere at all times. The question then arises, if their ideas are so right, and if they've always been right, how come they haven't conquered the world yet? There is only one possible explanation: conspiracy. Libertarians and fascists cannot explain their own failures, so they use all sorts of conspiracy theories to rationalize them. Someone - Jews or evil government bureaucrats - must be conspiring to smear and hide the eternal truth of libertarianism or fascism. New World Order, Federal Reserve controlled by Jews and Communists etc etc.
Right. A conspiracy of Jews is crushing the people in the Nazi case, and a conspiracy of bureaucrats is crushing the people in the libertarian case. The people cannot see their true interests, and it is up to the fascist/libertarian to bring about a glorious rebirth based on old, forgotten values and the practices of the people's heroic ancestors (that's 19th century free marketeers or the "Founding Fathers" for you libertarians, medieval heroes for the fascists). And this is to be done by undemocratic means - because democracy is evil - and against the will of the majority if necessary.
6.
The Cult of Righteous Violence. Libertarians and fascists love their guns, and they firmly uphold the use of righteous violence (that's "retaliatory force" in libertarian-speak) against their enemies. They don't see such "righteous violence" as a necessary evil, the way others may view a just war or a revolution. No, they see this violence as a good thing, something to be embraced and celebrated."