washington lead republican lawmaker warn tuesday congress able low u.s. corporate tax rate 15 20 percent range seek president donald trump unless controversial border adjustment proposal remain part tax reform proposal know border adjustability represent dramatic departure current u.s. policy would exempt export revenues taxation impose 20 percent tax import escalate war word measure oppose retailers oil refiners automakers house ways mean committee chairman kevin brady say would severe consequences tax reform u.s. competition trump job creation goals special interest succeed block border adjustability tax rat businesses would increase significantly propose 15 percent 20 percent rat undercut ability make america competitive texas republican tell u.s. chamber commerce brady speak day trump say administration try get current 35 percent corporate tax rate 15 percent rate propose 20 percent rate contain tax reform blueprint unveil last june brady house speaker paul ryan analysts say trump could trouble get rate much 30 percent without border adjustability provision would also go far pay low tax rat raise trillion revenues decade accord independent analysts house republicans bill provision way attract foreign investment keep u.s. company job move overseas something think clearly go get system re-set american job american businesses american company stay country ryan tell reporters powerful adversaries include billionaire industrialists charles david koch spend heavily support republican candidates conservative policies trump pour cold water proposal recent wall street journal interview call complicate worry would result bad deal america critics claim measure would raise consumer price goods apparel electronics gasoline potentially violate international trade rule house republicans say measure would neutralize high import cost strengthen dollar insist would pass muster trade authorities u.s. republican tie low business tax rate border adjustment