The chancellor must explain honestly that a better future for Britain cannot fund itself and that more taxes are inevitable, writes John Rentoul . But if she was overestimated when she took over the Treasury, she may be underestimated now E veryone knows that Rachel Reeves has made mistakes, Rachel Reeves included. One of those mistakes was to have claimed to have fixed the foundations of the public finances with last year’s tax rises . Another was to have chosen a tax rise – employers’