Yeah, the politics of it can get nasty. I guess they did that to keep the jobs or something.

Anyway, if you put a little bit of carbon into molten iron, you get steel. Traditionally that has been done by burning coke, and we’ve been using that for ages because it’s cheap and relatively clean in the pyrometallurgical sense. If you burned wood, oil or something else, you certainly could get the carbon that way too, but your steel would be contaminated by the rest of the periodic table, and that’s not great if you’re trying to build a bridge out of steel like that. Various carbon sources such as wood can be purified into coke, so there are options. It’s just that they haven’t been economically viable while normal coke has been available.

And that’s when we get back into politics. If it makes economic sense for companies to keep on polluting, they certainly will. The government gets to decide which business practices are rewarded and which are punished.