I am not sure I follow this moral stance vs nature. My computer is able to calculate billions of operations per second. That's more powerful than what the most brilliant mathematicians of the middle age could ever achieve. Should I feel guilty to use all that might to watch kitty videos on youtube? Everything we do has a cost on nature. When I eat a burger, a cow has to go. When I build a house, I don't want any bug or rodent in there. Yes tigers are heading toward extinction but guess what, I don't want to have to live with them when I walk in the countryside, so they will have to stay in zoos or national parks. To me the limit on pollution is to ensure that we do not generate a nuisance or hazard for ourselves or our kids. I have no sense of "fairness" vs nature.
The problem of cars in dense urban area has more to do with pollution (which electric cars solve) and space (traffic jams) than morality.
Your computer consumes barely no energy (in Joules). I'm not making a generalized abstract comparison, I'm making an energy consumption comparison.
When you eat a 10th of a cow per year (200g/day), you consume the same energy as one seat in a Paris-NYC flight, and the same energy as necessary to heat a house for a year, and the same energy as the Earth produces per year, per inhabitant. So, choose only one of those ;)
It's not about saving tigers, kitties, noise or morality. It's that the Earth doesn't produce that much energy, so we're not in a stable situation on the long term.
There are "footprint comparators" that you might have seen on the Internet: A European has a footprint of 2.5, which means it requires 2.5 Earths of wheat fields and uranium mines to feed, cloth and house everyone like a European. It takes 6 Earths to nurture someone like in the US.
So we can only sustain this pace of spending resources as long as we keep others poor (aka as long as Middle East/China/Asia don't enter into a consumtpion society). That's where I claim: We may have to take part with our cars in the future and therefore we'd better build our cities so that we don't need to move around that ton of metal per person.
The side effects of emitting CO2, nuclear waste, wars in the Middle East or costing an unsuspected cost through taxes are just different forms of the same constraint, which can be studied through energy consumption in Joules per inhabitant.
Our relationship with nature is symbiotic, not adversarial. We work better when we work to strengthen nature, not deplete it.
To give an example, there has been some concern recently about diseases affecting bees. Beside adding to the variety of the world, bees play an important function in pollination. Could we do this pollination artificially? Probably yes, but not without a considerable amount of effort, and bees do this work very well for free.
Besides this, I don't want the world to be dominated by a single species, for me the world is far richer and more interesting from the contributions of nature (if want to view yourself as separate from it, whereas really we're part of it).
The problem of cars in dense urban area has more to do with pollution (which electric cars solve) and space (traffic jams) than morality.