In some ways this article is credulous; it talks about Trump abandoning "traditional Republican concerns" about the deficit. There's actually no evidence the GOP ever cared about deficits, except as a stick to beat Democrats. 1/ washingtonpost.com/business/2019/…
And Trump has absolutely kept faith with the real Republican priority: afflicting the afflicted while comforting the comfortable. Still, the shift from fiscal austerity to stimulus now that Rs control the White House is striking 2/ 
After all, one overwhelming lesson of the past decade is that Keynesian economics works. In particular, austerity in a depressed economy really hurts. Exhibit A is the euro crisis, where a financial panic led to austerity in some but not all countries. Here's the panic: 3/
And here's what happened during the years of panic-driven austerity (measured by the change in the IMF's measure of the structural budget balance) 4/
The US didn't do anything that dramatic, but as the Hutchins Center estimate shown above shows, it did have significant austerity under Obama, which changed to stimulus under Trump. How much has that mattered? 5/ brookings.edu/interactives/h…
Well, here's a comparison: growth during Obama's 2nd term versus growth since the Trump tax cut. You may be surprised to learn that there was only a slight acceleration. And ALL of it (and then some) can be explained by the shift toward stimulus 6/
So I'd say that it's misleading to see all this as a change in economic philosophy. It's really about politically weaponized Keynesianism: austerity for thee, stimulus for me 7/
