That has a small links to my experience although only one of our family, originating in the English Midlands city of Nottingham, was personally in mining. He was a great-uncle who had worked "down the pit". I never knew him, but do not know if he had died early from "the dust" or something else... All I know is I have his Davey Lamp, in working order, though he had carefully removed its original labels that likely identified the mine!
Is the coal extraction President Trump wants to expand, mainly by deep mining or open-cast?
A huge difference, both in the numbers of miners needed and in the health and safety risks. Many fewer people are needed for open-cast quarrying, and they are much less exposed to the dust. They still face that hazard but it is easier to control, such as by enclosed cabs on the excavators, and wearing face-masks when drilling shot-holes.
Presumably underground collieries are still operating in the USA, otherwise much of the knowledge and skills will have been lost. Also, once a deep mine has closed, it is probably irrecoverable even if it still holds useful reserves; and once it has filled with water it can endanger any working ones nearby.
The father of one my former girlfriends was an ex-miner, and he suffered badly from emphysema due to years of breathing coal dust. When I saw him he was largely confined to an armchair, very weak, breathing with obvious great difficulty, as a long-case clock nearby gently ticked away his remaining years.
These days it is easier to reduce the risk by wearing appropriate PPE; as now normal in so many trades and industries; and also to monitor the health of employees. Gone are the days when even some workers thought themselves too "manly" for such things! In later years I worked in generally clean conditions, nowhere near a mine or quarry, but was still given an annual, simple medical including lung-function test because I handled some common but hazardous chemicals - I wrote the Risk Assessments for using them, too.
So if the prevalence of industrial disease is rising among your country's miners, I would ask why; although mining and quarrying are inherently very unhealthy trades anyway.
A friend who had worked in health and safety told me of trials at one colliery with helmets fitted with full-face visors ventilated by a small fan drawing air through a filter. He said at the end of the trials, the miniers did not want to give the helmets back!
As for a property-speculator's comments about men would far prefer to dig coal than make electronic equipment in clean conditions (or even work in a jobbing engineering factory - I have done both), I wonder if he'd asked any? He might have mistaken coal-miners' traditional loyalty to each other, even internationally, for them loving the work itself. They may have voted for Mr. Trump because he promised to revive their industry, but about the only attraction may be better wages than in factories.
I can't imagine many people now would want to work in a deep colliery unless there really is nothing else available. I think his policy is trying to make the nation more self-sufficient, but whatever the cost and without considering better than reviving dying industries.
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My Mam, the neice of that Nottinghamshire miner, was not impressed when in the bitter Miners' Strike in Britain in the 1980s, many miners were telling reporters their fears their sons would be unable to follow them and fathers before, into the industry. She said previously they all hoped their sons would find far better employment elsewhere!
[Her brother took the opposite view to that like-father-like-son narrowness. He banned his own son from following him into employment with the railways as he saw that industry as dying! So my cousin became a car mechanic instead... The railways? They survived, and now largely thrive.]