Before I answer the question, I went through the link. To understand what the paragraph you mentioned means, you have to read or put in perspective the whole paragraph. Let me quote the whole paragraph first.
At some moments, Junkyard Planet’s celebration of the ingenuity of the scrap grubbers and swipes at environmental and labor advocates can feel like an overly enthusiastic embrace of an economic system that distributes justice far less efficiently than it does junk. But the virtue of the clear, detailed picture, which Minter so ably provides, of the forces pushing our trash around and around the globe, is that it may yet help us decide what to hold onto and what to throw out.
I really do not understand what you are trying to convey in your points 1) and 2) it is a bit confusing, I would suggest you to try to rephrase it a little better. But I will try to answer the question from my understanding of what you might be looking for.
Let me start with your statement 3)
We think this economic system's ability to distribute justice is far worse than junk's ability to distribute justice.
First off all, the whole article is about the view of the book on the ethics of junk distribution i.e the US trying to make money of whatever they discard as waste. The books try to educate the reader that " things that we think to be worthless does in fact have economic value and is building up an industry on its own." Basically environmental and labor advocates say " selling/pushing trash to other countries is bad unethical, they even consider it to be "exploiting other countries", that is one point of view. The book tries to convey to the reader that, what these environmental and labor advocates think is trash is actually something valuable, something that can be recycled and something that can be used as raw material. Well if something is valuable to someone, anyone, then it cannot be considered trash right? so if whatever the US is selling to the other countries is not trash and indeed a raw material, then these environmental and labor advocates could be wrong in the way they are approaching the problem right?
two strong things I understand from this article is
1) environmental and labor advocates say it is injustice to push US trash to other countries
2) The book says, well if something is valuable, then it is not trash .
You need to understand these 2 points to understand the paragraph in your question.
So referring to your point 3), We do not think anything, and junk cannot distribute anything, be it justice or whatever.
Let me break it down sentence by sentence.
1) "At some moments, Junkyard Planet’s celebration of the ingenuity of the scrap grubbers and swipes at environmental and labor advocates can feel like an overly enthusiastic embrace of an economic system that distributes justice far less efficiently than it does junk."
Explanation :
This sentence says, At some moments/parts of the book, the way Junkyard Planet (the book) appreciates the way these business people who make a living of selling so called trash aka scrap grubbers ("celebration of the ingenuity of the scrap grubbers") and the way Junkyard Planet attacks/accuses or just disagrees with the views of the environmental and labor advocates ("and swipes at environmental and labor advocates ") can feel like the book is trying to say that selling trash is good even though the environmental and labor advocates can feel like it is injustice. reading the book can also feel like this scheme of making money is prioritizing "making money" more than the ethics of selling trash ("can feel like an overly enthusiastic embrace of an economic system that distributes justice far less efficiently than it does junk.")
The rest of the paragraph conveys the complete meaning
2) But the virtue of the clear, detailed picture, which Minter so ably provides, of the forces pushing our trash around and around the globe, is that it may yet help us decide what to hold onto and what to throw out.
Explanation :
But the real meaning/quality of the clear facts and details which Minter provides about the the way the trash is sold around the globe ("But the virtue of the clear, detailed picture, which Minter so ably provides, of the forces pushing our trash around and around the globe") is that , it can actually demonstrate to the reader that everything that they discard as trash/worthless actually is a necessity for someone out there and that the reader must give it a second thought before throwing out/discarding anything as trash, because it might not be worthless after all.
referring to your sentence 4), That is pretty much the meaning, you got it almost right. The book says this selling of trash is good, not because you make money out of selling trash, but because this process of selling trash actually identifies things that do not belong in trash and that can be recycled, and how it does not let things that can actually be useful, not go to waste.
It is basically trying to differentiate between "waste dumping" and "recycling"
I hope this helps.
