How so? Can either of you explain to me what you mean by this?
The first thing that comes to my mind is the french revolution. Now the french nobility were not libertarian (so please don't take this as me saying that they were), however one of the reasons it came about was because of
food shortages (I am sure we all remember the famous quote by Marie Antoinette, "let them eat cake"). One of the principals of libertarianism is very strong property rights. Now this is an extreme example, but if people do not feel that they are getting what they need out of life, they will ignore this principal and steal food. If things are bad enough, they will go so far as to topple a government (not the only reason for the french revolution, but one of them) in the effort to gain basic necessities.
Libertarianism relies on the existence of rules that are basically set in stone, such as the idea of natural rights, and relies on the idea that people would have to be innately moral (in terms of how a libertarian views morality) since we would have a simple government that does not do very much. However, history has shown that people will commit all sorts of evil to get what they want, whether it is through intimidate, exploitation, theft, etc. Libertarian government is very minimalist and would not present enough of a deterrent against the worse sides of our nature. Sure we would have law enforcement, but it wouldn't protect against even simple things like people putting poisonous substances in our food in order to turn a quick profit. And by the time action was brought against whatever company did that, people would already be dead, as happened in China recently with their pet food problem (they are not a libertarian government, but they have very loose controls over this sort of thing, so there is a similarity.)
In short, I think a purely libertarian government would not last long in a pure state and it would result in a lot of injury and death as people are as inherently immoral as they are moral.
I am not saying that libertarian ideas are bad, in fact on an individual level they are excellent, but I do think they need to be balanced with other ideologies to be workable society wide.
Also, there is no good voting option for me, because I would love to be a libertarian if I thought the ideas were workable without harm.