Specialization and the accompanying astounding development of productive technologies have lifted the standard of living around the world to unbelievable heights over the last three centuries. Trade—selling what we specialize in making and exchanging them for the wide range of things we need and want to consume—has made this possible. The pace of wealth creation and poverty reduction has accelerated in the last half century as the size of the markets in which we trade have expanded rapidly with falling costs and barriers to global trade. https://wcoats.wordpress.com/2014/12/18/free-markets-uber-alles/
But new technologies that displace older ways of doing things require workers and firms to adapt. New skills must be learned to replace the old, no longer needed, ones. Americans have been particularly adept at such flexible adjustments and thus have experienced greater increases in wealth and living standards than most other countries. No pain, no gain, as we might say.
Workers and firms have tried from time to time to defend their positions from the competition of other workers and from firms with newer and better technologies. Protectionist tariffs enacted to “protect” American jobs in 1930 deepened and prolonged the Great Depression. The closed shop autoworkers unions in Detroit seriously damaged the American auto industry. But generally Americans pushed aside these restraints on free markets and trade to the huge benefit of the population as a whole.
Nonetheless, such competitive advancements in our ability to produce more and more did require those with outmoded skills to acquire new ones. When the pace of innovation was measured, the required adjustments by workers and firms were easier to make. Younger workers would acquire the new skills from the outset while older ones would eventually retire. The turn over of firms, even very large and well established ones (Dell, Polaroid, Kodak, Motorola, Chrysler, Yahoo, etc.) has always been large in the U.S., continually making way for new and better ones.
The last half century has seen a rapid increase in the expansion of markets – globalization. While this increased competition and innovation has reduced poverty in the world at a never before seen rate, it has also increased the numbers of workers having to give up the skills they had refined and acquire new ones generally requiring a higher level of education. These adjustments have often been difficult for those having to make them, especially for middle aged and older workers. We seem to be experiencing a backlash from those forced to adjust.
“The experience of the past quarter century suggests strongly that the central factors of our era are not nationalism or militarism, but rather the two periods of radical change stimulated by technology and innovation during not one but two Industrial Revolutions. The first one began 175 years ago; the second, the information age, has now lasted about four decades.”[1]
Immigration is an aspect of globalization and the wealth creating impact of free trade. It raises similar but even more challenging tensions between freedom and progress and security and protection of the status quo. It also calls for careful management of the pace of immigration to soften the anxieties of potentially affected workers.
More liberal trade agreements facilitate globalization. Ironically President Obama, who opposed the trade agreements on the table when he first ran for the Presidency is now fighting for the adoption of the Trans-Pacific Partnership (TPP), while Hillary Clinton, never one to put the national interest above her own, who as Secretary of State helped start the TPP negotiations, now opposes it. And Donald Trump, who shouts out what ever passes through his mind at the moment, is currently strongly protectionist (i.e. protecting the status quo).
Rapidly increasing globalization has enabled an incredible lifting of living standards but has also increased the insecurity and costs to those displaced and needing to seek out new employment. We need to provide more effective assistance to these people. This should be the focus of our policy discussions, not closing off progress (protectionism).
[1] John Kornblum, “The Amerexit,” The American Interest, July 25, 2016
Warren's space 
If all countries had the same degree of welfare and labour market regulation, free migration would work well. However, it fails when some countries offer extremely generous welfare payments and discounted/free medical care, pensions, disability payments, family benefits etc (for instance Western Europe, Australia) whilst other (usually poorer) countries offer little if anything in the way of such welfare.
Plus many developed world countries have restrictions on people’s freedom of work and employ, by having tightly regulated labor markets which place a barrier to enter work for many migrants, particularly unskilled ones. In such cases, much migration is no longer largely driven by migrants’ desire to work, start and business and better themselves by such entrepreneurial activity. It becomes driven by the incentive of welfare.
Long term adverse consequences of large numbers of people living in a welfare culture, combined with the isolation that comes from not having to daily go to a job to work with people from their host country, results in disastrous social changes – lack of assimilation, the creation of a broad scale entitlement and dependency cultures. In turn, this can lead to serious problems – declines in prosperity and safety.
Warren, I would like to see you write on such matters.
Interesting discussion. I won’t pretend to know much about TPP except for its goal of free trade. I’m curious about Trump and Bernie being against it, Hillary having shifting positions (Warren, I know you believe she’s pandering), Kasich supporting it while being a popular multiple term governor in Ohio whose populace I assumed like Trump in large part due to his opposition…?
The gains from trade are so large that it is a mystery. My guess is that the gains are widely spread and thus seem small or modest to most people (cheaper consumption goods and jobs that people don’t associate directly with trade), while the costs (firms and their workers displaced by cheaper imports) are narrowly focused and strongly felt. In addition, we have not been that good at compensating the losers.