"Do deficits matter? Of course they do."

This is likely the only thing that we might agree upon in your article, but even that agreement comes from very differing perspectives. Assuming you view government's spending as something that, like a household budget, requires some "source" of dollars, revenue, I will assume your approach to the issue is honestly what you believe.

Deficits matter because they are the only "net" source of dollars in our economy. This is why they are demanded back when the government collects taxation and are necessary to "net" retire private sector debt or be "net" saved as a store of value. The national debt, an aggregate accounting of alll deficit spending since our nation's founding, is our money supply that represents the exchange of "real" resources for dollars, not an obligation that the private sector must repay.

Neither taxation nor bonds are "revenue" for the government that is the monopoly issuer of the currency. One cannot collect or borrow what doesn't yet exist and each dollar previously spent is already represented by bond issues. This means that spending by the federal government "funds" both taxation and bond sales, not the other way around. Our nation's currency is "sovereign" and self-funding by the same constitutional authority that gives Congress control of the pursestrings.

Deficits can be too large, but they can also be too small. If insufficient deficit spending is realized in the economy there isn't any money to fund growth or retire private sector bank debt. This forces the private sector to finance its own economy with private debt that relies on GDP growth to "roll over" debt. Every minor hiccup is such an economy will send ripples of default that can result in a tsunami if not corrected with federal money creation.