In the short term it would get passed on to consumers. In the medium term supply chains would figure out how to reduce shipping by road. In the longer term (in conjunction with other changes) we might be able to get larger-scale urban development on a more sustainable track.

If we could properly price externalities (not just road wear but also ground water contamination, CO2 emissions etc.) there are many parts of our economy which could be made dramatically more efficient and less harmful without that much overall change to human quality of life.

This would devastate the economy.

For example: Exxon mobil profits in 2017 were 19.7 billion. Fukushima cleanup costs exceed 180 billion.

There is no way to do what you are proposing without massive price increases in electricity, gasoline and virtually every other good. I wouldn't be surprised if when you priced all of this in you discovered that people couldn't really afford electricity anymore.

Also this economy would never be able to have exports because the price of producing goods would just be insane.

The truth is we can't afford the externalities without an economic implosion that would realistically end with an extreme political group taking control in the ensuing chaos and undoing everything you are proposing.

Mitigating climate change is essentially going to cost all of the direct profit ever made by all the companies in the fossil fuel discovery, extraction, refining, and retailing businesses.

Think 85 trillion USD, real value. That's about 1/3rd of the total current wealth of the entire world, by my back of the envelope calculations.

> For example: Exxon mobil profits in 2017 were 19.7 billion. Fukushima cleanup costs exceed 180 billion.

So you could cleanup one of the worst "spills" in history with a mere 10 years of a single company's profits?

That sounds perfectly OK.

Even better, it would have been possible to avoid that spill with that money and you'd probably have enough left over for a healthy profit afterwards.

The thing about externalities is: somebody pays, it's just not the person who caused them. Redirecting that cost back to the source would be a good thing. There would then be incentives to do the most efficient thing instead of the most wasteful thing. This would actually make everybody richer.

How much of our wealth is being wasted this way? I'm guessing that it's a lot.

Sure, but it might also have some other nice side-benefits, like favouring railroad expansion. Having transport by lorry being artificially cheaper is non-ideal for lots of reasons.

Actually, of trucks were taxed on a ton/axle basis instead of ton+axle basis, the net road wear would be dramatically reduced. Think 6-axle, tripple-tire trailers.

It's not that simple. HN readers could absorb the increase, but the poor can't.