From 1971, John Lennon rants against politicians that speak with rhetoric instead of being honest.
Rhetoric is like using language skilfully to convince someone to agree with a case or point being made. The arguments being made for an issue or cause may be weaker than they appear, when figures of speech and other creative ways of speaking (and writing) are employed.
Lennon just wants the truth. Of course, one suspects he would also reject the pure views of the politicians of his day he was protesting. On the other side, politicians may be limited in speaking their truth given political party allegiances, media attention, constituent views and other practical considerations such as finances.
All in all, the situation can breed cynicism about politics. However, speechifying is but one part of politics, and hopefully there is some respect for healthy political institutions such as an independent judiciary, free press and even an accountable legislature and executive branch of government.