Why would the US want to ease up on the basic principle of CBT?
I know it's boring reading, but the Republicans Overseas paper linked above counters the "CBT is a cash cow and repealing would be a revenue loss" argument with one that says TBT results in positive revenue. It offers a variety of reasons TBT is advantageous to the US. The ACA proposal attempts a revenue neutral position.
OK, perhaps a degree of smoke and mirrors, but the RO proposal balances income by changing the tactics for those living abroad with US source income. Anything from the US would have a flat tax withholding of 30% if it is FDAP income, which means altering any treaty that allows lower, or no rates on US sourced income. Non-resident citizens would be treated the same as non-resident aliens. (If I read all this correctly.)
https://www.irs.gov/pub/int_practice_units/WITCUP_15_1_01.PDFThere are some who are very upset about the TBT proposal.
EDIT: HuffPost article was from 2014!
Again, from a previous thread, can pigs fly? No one's holding their breath.