I have never really understood this. Even before I was a hardcore libertarian, I could not understand how so many people could be against capitalism and for socialism. It has been obvious to me since I was a child. Foreign policy wasn't always as obvious to me, as I soaked up the establishment opinions when I was young.
In regards to economic matters though, it doesn't even matter if you don't really understand any theories or concepts. All you have to do is look around the world. The places with economies that are relatively free market, like Hong Kong and Singapore for example, are generally rich countries. There are poor people everywhere in this world, but there is no question that countries like this are far wealthier and even poor people are far better off and have far more opportunity.
Meanwhile, places that practice heavy socialism are poor. There may be a few elite at the top who have a lot of money, but it is a very small percentage of the overall population. There is not much in the way of a middle class. Why does some poor guy living in a mud hut in India keep supporting the welfare state that has enslaved him and made him poor? He obviously doesn't know better. But doesn't the idea credited to Einstein ever take hold about the definition of insanity being doing the same thing over and over again and expecting different results? When people keep electing these socialist politicians to supposedly take care of the poor and they never see any significant improvement in their own lives or poverty in general, wouldn't they ever stop and think that maybe they should try something different?
Of course, perhaps it is even more foolish for a person living in a capitalist country who supports socialistic policies. At least people in the U.S. and other relatively free market economies have access to information. The guy in a mud hut in India may not have internet access. Most people in the U.S. and other relatively rich countries do.
It is also funny how people promote these socialistic policies and yet it is a complete contradiction to their own life. Of course, this is obvious with the Hollywood crowd, but I even see it with middle class people. They are completely inconsistent in that they advocate policies against property rights, yet they always want to maintain their own property rights. Their ideal world does not make any sense and there is no way we could ever go that far. Even the Soviet Union had a little bit in the way of market pricing, either getting it from other countries or seeing it in the underground economy.
I frequently like to remind people of what Murray Rothbard and Etienne de la Boetie pointed out. They said that all government rests on the consent of those being governed. This is true with any form of government, but even more so in a place with relatively free elections and free speech. If enough people realize that they are enslaved and wish to no longer be enslaved, then things can change overnight. But it does take either a majority or a significant minority to effect such drastic change.
While the libertarian movement has not generated enough numbers to significantly reduce government, I think we are on the right track. There are more libertarians today than there probably have been in the last one hundred years. And today's radical libertarians are very well-read and knowledgeable. I would venture to say, because of the internet and the benefit of seeing more history, that today's radical libertarians are more knowledgeable than the Founding Fathers of the United States.
Socialism is not inevitable. I think as the government continues to wreck the economy and create more unsustainable inflation and debt, that more people will start to examine the situation. When the government has to start defaulting on its previous promises, then people will be looking for answers. That will be liberty's big opportunity.