We all know that and we express that knowledge when we say: “a fish rots from a head down”, but usually we apply this sentence to social systems.
Why does GOP do what is does? => From:
I was born and grew up in a dictatorial or at least authoritarian country. And every day while growing up I was hearing on a radio, seeing on TV, reading in the press how free our country was, how smart and generous were our rulers, how evil were our enemies. At the time I did not know that all I heard, saw, and read was lies, which had been deliberately constructed to hide the opposite. But I had a very good education (ask - why?). Education which taught me to think. Eventually I was able to separate lies from facts. BTW: this experience eventually made me "a human BS meter" - a handy but sometime inconvenient ability.
What I hear, see, read now coming from conservative media looks very much similar to what I read up to 20 years ago in Russia. However, what I do not hear, see, or read is a smart and honest analysis of the social, economic, and political processes which have lead to the results of the 2016 Presidential elections, and a smart and constructive plan for progressive forces to lead the country.
That is why from time to time I take a "pen" and write my views on the matter (see links below).
Now comes the answer to the question in the title of this post.
Donal Trump, and all the forces he represent, want to transform America into Russia - politically, of course.
He, and the forces he represents, do not believe in the idea of democracy, do not like democratic institutions, and will try to do all he, and the forces he represents, can to weaken democratic institutions, to convert them into a cartoon, a facade, a powerless imitation of democracy. Thinking that American democracy is foolproof is wrong. No society is foolproof against incompetence, laziness, corruption, egoism, and greed. What was right 2300 years ago still stands as a rule; a society is as strong as many smart, direct, tough, and fair citizens it has.
BTW: Mathematically speaking, those four qualities are not terms, but factors, i.e. we do not add them, we multiply them, and if one is equal to zero, the whole product is zero.