Although a tax cut may have been a nice Christmas gift, it needs some follow-on spending cuts to work.  At best, Republicans have eaten their dessert first, waiting to eat their spending cut vegetables later; at worst, they will have increased the federal deficit by another trillion dollars or more.

By most estimates, even stimulating economic growth will not fully pay for the tax cut.  Republicans will now have to undertake the politically courageous step of cutting federal spending.

It will be difficult to make spending cuts without touching Medicare or Social Security, which President Trump has said are off limits. Meanwhile there is pressure to undo the sequester, automatic cuts on spending no one liked, but which have at least kept spending growth down. 

Ideally, Republicans would have disciplined themselves to do tax and spending cuts at the same time. Tax cuts may come and go, but the federal debt remains forever, it seems. And—without spending cuts—it grows.