Politicians often know the truth is too obvious and would show them, their proposals, and actions as unpopular, wrong, or even, evil. Euphemisms and word substitutions are used.
Paul Ryan, a Wisconsin congressman (R-naturally), wants to end, or at least change medicare. The repukes have always opposed social security, unemployment insurance, and other welfare programmes, including medicare. gwbjr who lied the US into war, and steamrolled opposition with the help of a compliant press, later tried to ‘privatise’ social security, by giving it to Wall Street. That failed. His poster programme, for his second term of usurpment of the presidency, failed. It is to be remembered, that his father ran for his second term on reducing capital gains taxes. It is obvious which constituency they represent.
Paul Ryan wants vouchers introduced. Instead of government paying medicare bills, people will get a lesser amount to buy medical insurance. This will decrease medical coverage, lead to worse health and earlier death, while making insurance companies richer. That's all fine with his party (Republican congressmen enjoy their government health care fine), but it does not sell that well with the populace (even some elderly teabaggers may figure that it hits them ).
So what does a bold, camera and microphone loving demagogue-to-be do? Well, first accuse critics of demagoguery; second substitute a new term for voucher, ‘premium support’, and then shy away from defining it. Let us see how many others of his party, and enabling media critters will broadcast this term of orwellian newspeak.