Republican initiatives and policies are directly responsible for the redistribution of wealth from the middle-class upward to the wealthy; thus causing a dramatically skewed wealth distribution that is damaging the U.S. economy and in the long run is very bad for the wealthy themselves. But there are not enough wealthy to elect anyone. Therefore the Republican party has had to take under its wing all manner desparate political groups that are Incompatible with each other . The party is coming apart at the seams. Trump is very likely to prove disastrous not only for the country but for the party itself. That's why we see so many establishment Republicans trying to derail him. Oddly, Trump is the candidate of the misfits, the lower middle class, the misanthropes, and those barely making it. Those who control most of the capital in the country can't stand him. This election may turn out to be a test of whether the old money really is in control or whether it is all an illusion .
I disagree. The primary cause of middle class wealth destruction has been free trade. The signature free trade deal was NAFTA, negotiated by one Bill Clinton. Until recently democrats were as eager as republicans to sign free trade deals. We have had 8 years of Clinton and 7 of Obama, during which next to nothing has been done to address unfair trading practices. I'm not absolving Bush, but you have had 15 years of democrats in control of the trade machinery and they have done nothing to protect US workers. They have however done plenty to make it tough to manufacture here, eg EPA and over the top pro union policies.
The other policy that has hurt the lower and lower middle classes has been unchecked immigration, legal and illegal. Illegal immigration has hurt the lower class, but legal immigration has been a gut punch to many people who had decent middle class jobs in fields like computer programming. While republicans have certainly done nothing to stem the tide, democrats in search for new dependency voters have been the ones pushing immigration.
The other thing that has sharpened income disparity has been the incredible rise in C suite compensation. The ratio of average worker to CEO pay has blown all out of whack since Clinton took office. If the democrats are so damned concerned about income disparity, you'd think they would have addressed it during their 15 years in charge of the White House, many of which years they controlled both houses of congress. Yet they did bupkus. They did manage to bail out the banks and car companies and used bailout funds to pay bonuses to execs who should have been facing indictments.