During the first Trump campaign, the House GOP put forward a proposal for a DBCFT: http://abetterway.speaker.gov/_assets/pdf/ABetterWay-Tax-PolicyPaper.pdf, sometimes called the "Brady-Ryan tax plan". For an explanation, see here: https://taxfoundation.org/research/all/federal/understanding-house-gop-border-adjustment/ and here : https://www.brookings.edu/wp-content/uploads/2017/09/5a_auerbach.pdf. This was ultimately abandoned in favor of a less radical reform which become The Tax Cuts and Jobs Act (TCJA).
In this campaign, Trump has spoken, often, of tariffs. A DBCFT is a good compromise to tariffs in that in very general terms it acts as a cashflow tax, i.e. a VAT net of wages, in a domestic context, but it taxes imports but not exports (also similar to many VATs), and is widely considered as a much better tax policy.