Every single proposal for a national sales tax, consumption tax, or 'flat' tax put forward by the right has been shown over and over again to not be regressive

Every single proposal for a national sales tax, consumption tax, or 'flat' tax put forward by the right has been shown over and over again to not be regressive - usually through the implementation of prebates (literally a check written to lower income people every year/quarter to cover a portion of the taxes they will pay). Whether or not these schemes would work is debatable, but to claim that they show an MO of regressive taxes is just false.