The Atlantic article is great.
Just to add some info: This tax reform would shift the tax base from income ("comprehensive income tax base"/"Haig–Simons income") towards consumption (a couple of examples for consumption base taxes are european VATs, national retail sales tax or something with the fancy name Hall–Rabushka flat tax).
Once you change the tax base to consumption, you have to decide whether you want an origin or a destination based consumption tax.
The Tax in the Ryan plan is a destination based tax. Usually that is seen as a positive by politicians, because it stops tax competition ("race to the bottom"). Thats one reason why progressive economists would/should like this tax.
Overall there is broad agreement between economists that shifting towards a consumption based tax base is beneficial, because it creates less distortions in the markets.
Here is another article that might help to understand this tax reform:
https://www.forbes.com/sites/jonhar...d-corporate-taxation-in-the-u-s/#5b64de124405
Here is a paper from one of the economists who is closely associated with the idea:
https://www.americanactionforum.org...der-Adjustments-in-International-Taxation.pdf
from this paper:
this might need to get fixed, but that would be do-able.
It is quite hard to argue, that this tax reform is bad regardless of your political position. It is a step in the right direction. Obviously not for the reasons, that Trump is talking about. He is just confused about the effects, which is probably a good thing. He just wants to have the word "border" in the name. I have doubts that the $ would adjust like explained in any of these analysis, but that is a separate issue.