The primary problem destroying the middle class is the commoditization of labor. The vast majority of Americans and humans in general earn a living by selling their time. Labor is both a competitive market and a segmented market.
So, if your skills are highly specialized like those of surgeon or a plumber and the available supply is limited, then you can command a high price for these essential skills.
However, thanks to containers, manufacturing skills are now available globally and the only barriers to competition for these skills is the modest cost of shipping. That means if you want to raise incomes workers, you must take steps to insulate from global competition by restricting the ability to import goods from foreign goods. That has impacts on consumers, but it raises incomes for workers.
Likewise massive waves of illegal immigrants drive down wages in areas that illegal workers can find employment. House painting in this country costs a fraction in parts of the country with large numbers of illegal immigrants compared to areas of the country without a pool of illegal immigrants competing for painting work.
While the first two forms of labor competition (offshoring labor) or importing workers are obvious, less obvious is automation. Automation in many cases not only speed up production, but it also reduces the skills needed to perform a task. A simple example can be seen in Starbuck's today. Thirty years ago, baristas needed skills to make good expresso coffee, today baristas press a button, and the machine does all the work. Clearly the skills to handcraft an expresso drink are worth more, than the skills to press a button. By reducing the skill level associated with a job, you force it into the largest labor pool available and thus reducing its value.
To grow the middle class, we need to limit the competition from foreign labor, restrict immigration to a level that does not overly depress wages, use education to optimize the skills of our labor force, and increase job growth in order to put pressure on the supply of labor and force employers to pay to secure it.
Another problem is taxes. At the end of the day all taxes are paid by workers and owners. The more our government spends, the more it must tax directly or indirectly the citizens of the country. Presently, a sizable share of that taxation is through printing money and thereby devaluing living standards through inflation. The more of our economy the government takes, the less of it is left for workers and owners. While the government tends to distract citizens by promoting class warfare, the truth is that if the government spent less and productivity improved, standards of living for all Americans would rise, if we could protect their wages from foreign competition.
But given the aging population and the increasing number of citizens and illegal immigrants requiring goods and services, those goods and services must come from somewhere and a portion will come from the middle class reducing their standards of living if we can't increase the production of goods and services to offset the government's "bigger bite" of GDP.
A secondary approach to boosting the income and net worth of American citizens is a forced savings program. If every American had 5% of their income withheld and depositing into a self-directed private sector diverse fund, it would force them to build wealth. If access to this money was severely restricted prior to age 65 and then annuitized, it would create an additional source of wealth in the nation and income for the elderly (allowing them to maintain their lifestyles in retirement).
Amont the ideas suggested, some make sense others do not. Affordable access to vocational training and higher education already exists, the problem is too few people use that access to acquire valuable skills. Redesigning education to produce citizens prepared to fill high paying jobs in the marketplace rather than provide a general education would be a good first step.
For the most part benefits are portable these days. Employee bargaining rights only work if you can protect employees from offshoring their jobs.
Public infrastructure investments and corporate and progressive tax policies will do nothing to strengthen the middle class per se. That is not to say they are good or bad ideas, just not relevant to rebuilding the middle class.
As example, as someone that has done corporate strategic planning, higher taxes are funded first by consumers (higher prices), then by employees (lower wage increases, fewer FTEs, or offshoring labor to save money), and only as a last resort by the company and its shareholders.
We are facing an ideological war. But throughout history, class warfare has never worked to raise incomes of the middle class or the poor. Instead, the key to increasing the standard of living of workers is to increase GDP, restrict global competition from driving down the value of their skills, and reduce the amount of their income the government takes to fund is spending through taxes or inflation.
