I'm not sure, however, how you can say that working in a steel mill that would not be in business if it weren't for tariffs on imported steel comes with any dignity. Sure there is the dignity of showing up for a job and doing good work, but ultimately that job is being funded by welfare, and is itself a handout being received by the worker.
The economy is a rapidly changing thing, and there is no reason to believe that any industry that is thriving today will still be thriving in a decade.
But rather than undertake the worthy and challenging task of positioning our economy (via job training, entrepreneurship, etc.) to be resilient to change, we prop up industries that are much more efficiently done elsewhere.
Consider how this would have played out in the early days of the automobile. Soon most of the blacksmiths who had been gainfully employed putting shoes on horses would find themselves out of work because people started preferring motorized cars to horse-drawn transit.
By your logic, we should have idealized that horse-drawn era and should have put policies in place to guarantee that all of those blacksmiths were able to continue the dignity of their trade even though their skills were demanded much less.
While there is something nostalgic about the days of horses and pre-industrial society, most of the important humanitarian (moral, etc) advances that have been made since then have been due to the proceeds of the improved economic output of an industrialized economy.
What happened to those blacksmiths? Some probably ended up out of work and had to struggle to survive, while others likely transitioned their skills doing metalwork in the industrial sector.
All humans have value as humans and I believe that the vast majority have strong work ethic and a desire to support themselves and their family through work and discipline.
Nonetheless, as the economy changes rapidly, we find that we (industrialized nations) have lagged significantly when it comes to our educational system. Our modern schools still do many things the same way they were done in a one room schoolhouse.
There are many reasons why this happened -- I'd argue that the biggest one was the state takeover of education during the industrial era to free up more workers by providing free daycare (not education). So the root cause of worker displacement is connected with industrialization, but it is due to state monopoly power and the destruction of liberal educational ideals in favor of daycare and rudimentary skills training. In other words, we should not teach people a trade we should teach them how to learn for themselves.
Our educational system today is still very trade oriented, and that creates calcification in the economy and is ultimately a grave threat to national security.
But politicians will of course prefer to prop up dying factories in dead industries in exchange for primary votes rather than tackling the much harder problem of figuring out how first world education should work in 2018.
I'm not going to pretend to be an economist, serious or otherwise, so I won't dispute this notion.
Tariffs appeal to the naive idea that trade imbalances between two nations are a bad thing.
This, however, needs some augmentation.
Tariffs are a tool. Like most tools, they can be used multiple ways.
Tariffs aren't only for balancing trade. The most common use is to punish another country economically for engaging in an action, such as doing business with the wrong people, or imposing other tariffs.
Tariffs are also used to create jobs. To me, this is the most important function of a tariff, and one which the current American has very visibly implemented repeatedly.
A high import tariff on a particular type of product can help create jobs in that sector domestically.
There are vast numbers of people in every nation who are not able to — and will never be able to — code a program, or invest in the stock market, or found a startup, or work a robot assembling a car. But they can snap plastic forks off of a mold in a factory, or drive a forklift in an aluminum plant, or mix the concrete that paves the roads you drive on every day.
These are actual, real human beings who deserve to have jobs and dignity.
In SV this these people are often dismissed as undesirables who just need to be "re-trained." But a significant percentage of the population cannot be re-trained, for various reasons ranging from mental capability to physical limitations to family obligations to things you an I will never experience.
The real re-training that has to happen is in the chattering internet classes who think the majority of the nation is like them, and it's OK to leave everyone else behind because... progress.
A tariff won't create the next American entrepreneur. But if it keeps 10,000 people from becoming homeless, I'm all for that.