I think Mark 12_30 is on the right trail. The only way to understand Tolkien's feelings about the machine is to look at him in the context of his own historical time.
Helen's comments on WWI are very apt. I would add just one other point. There was also the element of propaganda, which was rampant on both sides during the Great War. As the young men signed up for duty, they were barraged with a host of patriotic posters and newspaper stories. These were blissful representations of a war that did not exist: posters that showed sports clubs enlisting en masse as if the war was just a continuation of their usual Sunday afternoon soccer matches and comradrie; pictures of pretty maidens in fancy frocks serving tea to the young men as they departed on the train; cigarette commercials where the soldiers blissfully relax in the trenches and even stand up in the middle of the battle field to take a smoke.
The problem is that none of this bore any relation to reality. In Tolkien's mind, the machine and its use became linked with deception. For he and his friends had surely been deceived when they went off to fight the War of the Machine. This is the same connection we see in the Lord of the Rings where those with power over machines were inherently duplicitous, smooth talkers who loved machines, people who could not be trusted. Saruman clearly falls into this category.
Secondly, I think you have to see Tolkien's environmental yearnings in the context of his time. I am not saying today is perfect. Far from it ! We can still see evidence of greed and indifference and their sad impact on our world. In some parts of the globe, the bleak necessity to survive channells folk into the destruction and neglect of the environment. Yet there is one critical difference between now and then. There are many environmental groups around who do speak out and companies must make some attempt to comply with government regulations or else they run the risk of lawsuits. It's even possible to go to college and study ecology or environmental sciences.
Very little of that existed at the time Tolkien was writing. I'm sure he felt like a lonely voice crying in the wilderness. This probably accounted for some of his natural stridency in this area. Frankly, I felt the same way in the 60s (and that was long after JRRT's writing), and part of that is still with me. For example, I can remember when Rachel Carson's Silent Spring first came out in 1961-- people were absolutely shocked to hear what she had to say about pesticides and how they ran inside our very bones and the lands and waters of the Earth. In fact, the main theme in Tolkien that the sixties college students responded to was his championship of the environment. Students felt that he was one of a very few authors who understood how they felt. (The religious themes, on the other hand, were not regarded as so central as they are today.)
My guess is that, given this lack of ecological awareness in the general society, an awareness that we take for granted today , Tolkien did not regard his opposition to the machine as "looking backward" or the sin that the Elves were prone to. He regarded it as taking a strong and rebellious stand against the forces of evil, the forces of indifference that surrounded him everywhere. I understand why he could make a reference to "bombing" factories and power plants (not in seriousness, of course). When you believe something is right yet no one pays the slightest attention, and it seems as if there is no hope to change things by acting through the system, you begin to take on an increasingly belligerent stance!
I am sure this accounts for a good deal of his impatience. Intellectually, he was aware that not all "machines" are evil, but he had seen too much abuse and it affected how he felt.
Just take a look at what actually happened in the time that Tolkien lived. In the first fifty years of the 20th century, there was more land in England stripped of trees than had occurred in the previous four centuries. By the time Tolkien died, just a little more than 10% of the countryside was still forested, and most of that was with non-native conifers. (You'll notice that JRRT never mentions conifers among his favorite trees!) With the advent of the motor car, he saw habitat after habitat destroyed by the advent of 'super' roads. Yes, there was certainly economic reasons why all this happened, but it was a tremendous price to pay.
We all know about hobbits and mushrooms. Yet the sad truth is that ,during Tolkien's life, wild mushrooms were dying out all across Europe, a process that has continued after his death. Seventy species of fungi are now extinct in Europe and another 600 have become "uncommon", including the wood blewitts, giant chanterelle, and penny-buns or cep. Cep once grew all over England; now they can only be found in very remote places. Why is this happening? The cause is habitat loss, combined with acidification from increased levels of nitrogen and sulphur in the air, and heavy metals in the soil. No wonder the "machine" sometimes made Tolkien angry, and he displayed an ambivalent attitude in his writing.
(Child gets down from her soapbox....
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