After many decades of impressive and relatively steady increases in the standard of living (increases in real per capital income) of all quintiles of the American income distribution, since 2000 all quintiles have lost ground. In the run up to 2000 incomes in the top quintile increased more rapidly than those in the lower quintiles resulting in a less equal distribution income.
The mean real incomes of each quintile are lower now (2014) than they were in 2000. However, the percentage decline has been larger for the middle and lower income quintiles (see table below) leaving the more unequal income distribution in place. Some of the relative gains of the top quintile are attributed to the growing premium for higher education, but as claimed by the Occupy Wall Street demonstrators, some have not been earned by providing higher valued products.
Most of us do not resent and in fact are grateful for those whose wealth resulted from inventing and giving us products we greatly enjoy. However, we are rightly angry at both political parties for increasingly supporting crony capitalists—those who benefit from their connection with and influence on the government—who benefit at the expense of the rest of us. They are capturing economic rents at the expense of the rest of us rather than enjoying the fruits of greater productivity.
The broad political consensus in the United States that we are each entitled to the wealth we each create, but must fairly share in the cost of providing our national defense, public goods and a satisfactory safety net for the poor, seems to be falling apart. In the economic sphere, the left increasingly favors one group, the working class represented by labor unions, against the professional and entrepreneurial classes. Classical liberals (i.e., economic conservatives) champion fairness – a level playing field – and the freedom to get rich if you work harder, or create a better product, or a more efficient way of producing what people want. They champion measures that facilitate entrepreneurship and economic growth without much regard for its impact on income distribution. Trade – globalization – is an essential part of promoting economic efficiency and thus growth, allowing, if not forcing, firms to shift resources into goods for export in which they are relatively more efficient in order to pay for the cheaper imports enjoyed by the average middle class consumer.
The Republican Party more so than the Democratic Party, though not by much, has increasingly been failing to preserve a level playing field in various areas (Wall Street, defense industry etc.). But the embrace of protectionism offered by Donald Trump reflects either class warfare or ignorance of globalization’s enormous contribution to our standard of living. The big trade and industrial unions of old—think of the United Auto Workers in Detroit—followed a different drummer. They were not interested in fairness but rather fought to bring economic rents (monopoly returns) to themselves at the expense of other workers via a deal with their employers to create, defend, and share monopoly returns. This worked with the auto industry, where auto workers earned at least double the prevailing wages for nonunion workers with comparable skills as long as GM, Ford and Chrysler could hold off competition from German and Japanese (plus a growing list) auto producers via a combination of tariffs and safety standards. Globalization gradually destroyed this monopoly arrangement and almost killed the American automobile industry until U.S. automakers relocated to southern, non-union states.
While good working conditions are win win for workers and employers, pushing up wages above their competitive level either drives firms to other locations (non union states or abroad) or kills them all together. Voters supporting protectionist policies either don’t understand that they lower the standard of living for most people (here and abroad) by lowering the overall productivity of workers or they seek to exploit monopoly rents for themselves at the expense of other workers.
Such thinking was dramatically illustrated by the recent strike of workers at Tesla Motor’s giga battery factory project in Nevada. As reported in the Washington Post on March 2: “On Monday, hundreds of workers walked off their jobs at the giant battery factory that Tesla Motors is building in the desert outside Reno, Nevada. It wasn’t your typical picket: They weren’t protesting bad working conditions, or making a show of force around contract negotiations. Rather, they were protesting other workers — specifically, the fact that they were from somewhere else.” Their complaint was that workers from out side Nevada were willing to work for less than the $35 per hour that members of the local union were making. These were not “foreign” workers from South of the border. These were workers from Arizona and New Mexico. The out of state workers obviously found their “low” wages with Tesla in Nevada better than the wages they would receive staying at home so they were better off coming to Reno.
The Post further reported: “That dispute explains an important debate underway right now in all sorts of skilled trades: Builders say there’s a labor supply problem, which needs to be fixed by bringing more people into the field from across the country and across the border. Worker groups say there isn’t a supply problem — it’s just that builders aren’t paying enough to make the jobs worth someone’s while.”
Trump’s pledge to protect America workers from cheap Chinese and other imports so they can produce them in the U.S. at a higher cost, is bad economics and bad policy. He is pledging to benefit one group of workers at the expense of other workers and at the expense of the standard of living more generally. This is not what the Republican Party has stood for in the past and not what it should stand for now. It should stand for fairness and equal opportunity for workers and entrepreneurs to benefit from doing things better and thereby raising their incomes and the income of the nation. The principle of fairness is widely held in the United States but has always had to battle for dominance against the temptation of the zero sum claims of special interests for government to serve their interests at the expense of others and at the expense of fairness. Donald Trump and Bernie Sanders are appealing to special rather than general interests at the expense of fairness.
Warren's space 
“I have no respect for the passion of equality, which seems to me merely idealizing envy.” Oliver Wendell Holmes