For clarity, I'd like to focus strictly on Libertarian *economic* policy. The rigid, dogmatic belief in absolute, unfettered Laissez-Faire Capitalism. While their social policies and foreign policies are nominally progressive/humanitarian, they do a total pro-Von Mises / pro-Austrian School disconnect WRT all things related to economic policy.
75% of US presidents have been Republican. The rest, Democrat. The US (and Canada) is now a 2-party monopoly of rightwing Neo-Liberalism and rightwing Neo-Conservatism. Partly because of this, many are cynical of the role of federal government. Many dismiss the role entirely, as if government is permanently and inherently evil. But they are basing their sweeping attempt at federal government invalidation BASED on the precise effects of Neo-Conservative and Neo-Liberal policy. How many Presidents (or Prime Ministers) have been progressive social democrats or progressive democratic socialists ? 0. How many times has the NDP formed Federal Government ? 0. How many times have the policies of Kucinich (or his equivalent) been implemented in the US ? Never. North America is a haven of rightwing economic policy insanity.
But the Libertarians and diehard Capitalists decry North America as "not capitalist", almost religiously. To counter that, let's just measure the after loophole annual personal income tax rate US Billionaires have paid over the last 30 years and measure the percentage of industry which is nationalized (since 1980). Then, factor in how much of tax revenue is redistributed to the poor. The fact is the US is 85-90% capitalist. All economic barometers point to this. So for Libertarians and diehard capitalists to say the damage in the US economy is due to socialism or a left-leaning federal government is obviously false. It's due to a predominantly capitalist system. If the egg you fry is burning on a stove top set to 8/10, you don't say "If only I would have turned it up to maximum, the problem would have been averted".
All barometers and economic indicators point to the reality that the US has been the most capitalist nation in the last 30 years (in the western, industrialized first world context), and the statistical manifestations found re: child poverty rates, infant mortality rates, education outcomes, life expectancy, personal bankruptcy rates, homicide rates, incarceration rates, etc. clearly prove that the more economically capitalist the system is, the more it punishes the bottom 1/3rd of income earners. Those stats are far more favorable in countries which have actually HAD some social democratic federal governance, and the policies of Layton & Kucinich applied nationally (Norway, France, Sweden, Finland, Denmark, Netherlands, etc.).
So, the danger of Libertarian economics are 2-fold. They serve and embolden the top 10% of wealth earners even more rigidly than is now the case in North America (causing even more child povery, bankruptcy, and general falling through the cracks) .... AND ... they spread a very dismissive attitude towards any notion of *good* federal government policies. If you happen to see Ron or Rand (as in Ayn Rand) Paul and hear their constant looping of "I don't think it's the federal government's role to be involved .... government is evil...", then you'll notice the religious, dogmatic, circular dismissivity.
It should be noted that there are really only 2 institutions of big power in a society : business and government. We know that business and the free market do not embrace or employ things or ideas which are non-profitable humanitarian ventures, so that leaves only the government as the remaining powerful social institution which can help people's lives. We can rule out all Neo-Liberal and Neo-Conservative politicians as providing any relief, yet somehow they keep sustaining their political monopoly over all of North America. Only a different set of federal policies can address the adverse effects of decades of rightwing, pro-capitalist North American government.
Please, vent your anti-Laissez-Faire-Capitalism views here.