When, in the 30's? 
Coal mining is much more safe than it used to be.
And please, knock it off with the climate change bullshit. The climate has been changing for billions of years.
Much more recent.
I had an Uncle who worked the mines. Died from it. Black Lung is no joke.
As a matter of fact, black lung is on the rise compared to the late 90s.
The reality is that coal is a product of years gone by and the jobs will not return. Coal is a fossil fuel that was needed when steam engines were the most powerful things to move cargo. Today it's just not the case.
I do feel bad for people who believe that coal will make some triumphant return just because Trump is President. It just will not happen. While many may hate some of the politicians and call them liars, there were some over the past couple of years who were very honest that the coal industry is dead and that moving those people to the newer fields of renewable energy is where the job growth will be.
That's just reality.