We are not turning into a poor country because of "greedy rich". It has always been at the behest of politicians, they don't even need to be corrupt. The simple matter is the political class, the true one percent, have been disconnected for years from the population as a whole.
It is far worse for Democrats than Republicans. Regardless of how we see Trump the simple fact remains, the Democratic party has ignored its based for years. Nothing is more telling that the open mockery that was made of the Republican party for having so many candidates in the primaries, how did that become a bad thing? At least they let their base choose. By doing so a lot of independents also lined up on their side as well.
Yet what happens when the American people push back? The system does its best to clamp down or usurp the attempt. the Tea Party really did start off on its own but was eventually co-opted by national interests. Before it was there was no shortage of negative comments about it from all sides. There was also a dearth of attempts to limit campaign funds because neither party wanted a repeat where they did not control all dollars in politics.
The issue facing America is that it needs more than a two party system to go forward. Prior to the current President the majority of past Presidents worked for their party first and rarely for the people. This is true of the majority of Congress, laws are passed to protect their power, their party. When laws don't do the trick they resort to dividing people through speeches, innuendo, and out right lies. Politicians derive a lot of power by dividing people and then stepping up that they can "fix it" by punishing one side or another.