I think the mistake you are making is to equate the left or left-leaning policies with with a better society.
Comparing to other countries and looking at a ranking system in Wikipedia is also a mistake. We are not the same. You are not comparing the same things. There are societal, cultural and historical differences that have a huge impact on the results of any given policy. Also, our economy is much, much larger and diverse, in absolute terms, than that of most countries.
The Nordic countries tend to be used as a model to support distributive socialist positions. The problem is that you just can't draw parallels between these nations and the US. Our system, our people, our politicians, our industry, our geography our social construct is very different from theirs.
Here's an interesting paper from MIT discussing some of their challenges:
http://economics.mit.edu/files/5726
Here's an excerpt:
"The two phenomena taken together imply a tendency for total spending on welfare services to rise faster than GDP over time. As long as the production of these services remains in the public domain, or as long as they are tax-financed, the tax burden must also exhibit a tendency to rise continuously with GDP. This
is a problem of the welfare state that we have been living with for decades now. However, starting from an already high tax burden, the efficiency cost of further increases in tax wedges will at some stage rise steeply, and high taxes will eventually cause serious harm to employment and growth. It seems to us that we may be close to a critical point where the deadweight losses due to high tax wedges and, particularly, their effect on labour force participation rates start to bite seriously. This is particularly so in view of some of the consequences of globalization and demographic change."
And that's the problem. You can make it work for a while in some societies, but it is not a sustainable long-term model. Greece being a bad example of this.
An almost trivial exercise using Excel can easily demonstrate how flawed these ideas tend to be.
The Nordic countries can, to a large extent, live the way they live thanks to a lot of what has come out of "the west". Look around your home or office. All of what you see is the result of capitalism at work. From your clothes to your furniture, watch, phone, computer, car, etc. The life saving devices the Nordic countries use to treat their population would not have existed had the entire world operated as they do. They are all the result of capitalism. In other words, socialist societies, could be argued, have been able to keep the status quo thanks to capitalism.
That's one view. The other is purely mathematical (the Excel spreadsheet model).
I find that anyone who's run a non-trivial business for many years eventually gains an understanding that seems impossible to get as an employee or as a government worker. When you run a business you very quickly understand that income distribution is a formula for disaster. It is not sustainable and it does not, despite how it is being sold by the left, result in a better society.
If you want a better society to live in you owe it to yourself to truly and objectively look at what the welfare state has done to our country. The war on poverty is decades old and our poor as more miserable than ever. The war on education, same thing. All of these government programs create more misery than wealth.
Look at the contrast between a SpaceX and traditional aerospace contractors. Amazing! And, frankly, you don't get the full sense of the difference until you actually walk through SpaceX --as I have-- and see how different things are when compared to traditional government contractors. It's almost the difference between being motivated and being brain-dead.
If you want a better society then you should want more freedom, more entrepreneurship, more SpaceX's and less of anything that has to do with the government controlling your life and your business. We want them to manage our country, maintain roads, enforce reasonable laws and regulations and create solid and productive relationships with other countries. If you truly want a better society you ought to demand results, efficiency, compassion, fairness, frugality, stability and a whole host of things out of our government that we have not had for over 50 years, regardless of which party has been in power.
To be sure, the topic is complex, perhaps well beyond our comprehension. All I can ask is that you don't form your opinion based on what they tell you and a single world view. Look at what they have actually accomplished. I am not a Reagan fan-boy but the question he asked in a debate way-back-when is powerful and should be applied to any ideology from any party: Are you better off today than you were <insert date>. Look at Democrat and Republican promises and ideology and see what they've accomplished after decades and decades of being in power. Are poor people really better off today than fifty years ago due to government programs or due to progress created by a mostly free capitalist society. I think the answer is obvious, just remove everything they have and can do today that is a result of capitalism and you have the USSR.
Just think. Don't follow. Lead.