Kristoff's REAL argument
Let's look at what the author's thesis or claim is--not at what the solution to the problem is.
Look at the article's title. That's always a directive: the title points out the topic of any piece.
Second, look at the weight of the writing itself: 14 paragraphs deal with his claim that income disparity in the US is huge, so significant that we qualify as a "banana republic" (define this term in your work), and indeed are worse than some. He cites Argentina.
Are his facts accurate? Is his position or claim accurate? Do we in fact find ourselves in this situation?
He writes: "But there is also a larger question: What kind of a country do we aspire to be? Would we really want to be the kind of plutocracy where the richest one percent possesses more net worth than the bottom ninety percent?"
That should bring us back from the small, secondary issue of tax cuts and benefits, a topic that takes only 4 paragraphs (4 out of 19). His secondary point here is that in the face of this alarming separation of rich and poor, let's be sure to make the sensible policy changes that help solve the problem, not worsen it.
The fundamental claim (his argument) remains: we are a plutocracy, not a democracy, a hedge fund republic akin the to old banana republics of old. that's what you argue about--yes, or no?
Does this help?