> those requirements just get gamed. ... [J]ust tax fuel (or emissions etc), and consumers will institute their own personal fuel efficiency requirements.

1. People — individuals and companies — game the tax system at least as much as they do pollution regulations.

(As part of that effort, certain political elements are always trying to defund the tax enforcers (e.g., the IRS) so as to make it easier for scofflaws to get away with such gaming.)

2. Politically, tax hikes are always harder to enact — and to keep in force — than standards for products and behaviors that voters can see are beneficial to them (e.g., pollution prohibitions).

> 1. People — individuals and companies — try to game the tax system at least as much as they do pollution regulations, and probably much more so because tax obligations are largely self-reported with only sporadic auditing to catch cheaters and gamers.

> 2. Certain political elements are always trying to defund the tax auditors (e.g., the IRS). We might well ask why that is.

Tax the petrol itself. That works reasonably well in most of the world. No need for complicated individual audits etc.

> 3. Politically, tax hikes are always harder to get through Congress — and to keep in force — than sensible standards for products and behaviors that voters can see are beneficial to them (e.g., pollution prohibitions).

I don't know. We kicked off the whole discussion because the standards you have are NOT sensible.

> Tax the petrol itself. That works reasonably well in most of the world. No need for complicated individual audits etc.

True — but see my #3 above (political problems), and then add 3.1: Special-interest groups, which donate heavily to politicians' campaigns, always lobby for tax breaks of various kinds, e.g., tax deductions (at the federal level) for state- and local sales- and property taxes.

> just tax fuel (or emissions etc)

No, because that harm small fun sports cars. The problem is big cars. Just ban big cars.

Small fun sports cars don't cost that much in fuel do they? Ferrari and Bugatti owners are pretty insensitive to fuel prices anyway.

Fuel tax is the best solution. Pay as you go.

More fuel you consume more emissions you produce, more distance you go, more road your wear occurs.

Do you want to get 8l V8 engine? Fine, just pay your fuel taxes.

Each US state has a gas tax already. Higher gas prices also don’t seem to stop people from buying giant trucks and SUVs.

A reasonable well optioned truck is $75,000. People who can afford to spend that are immune from high gas prices.

You'd be surprised how many people look only at the monthly payment amount and ignore other financial concerns when deciding on a vehicle purchase. And perhaps with some terribly long loan term like 72 or 96 months they can get that payment to "fit" in their budget.

You'd be surprised how many people don't even consider the monthly payment. Not uncommon where I grew up to see guys making $50,000 a year driving $70,000 trucks. Because they "need it for work".

$75,000 is waaaay beyond "reasonable" and "well optioned." I got my used Ford F-150 with about 220,000 miles for about $3,000, but there are plenty of actually reasonable trucks with good options in the $15,000-$30,000 range. And I'm definitely not immune to gas prices, I only take my truck when it's for something that I can't reasonably do in our Elantra, or when my wife is out somewhere in the Elatra and I need to drive somewhere.

Make gas ten dollars a gallon and people will consider a more efficient car.

By global standards, the American states have very low gas taxes.

What about the electric SUVs?

You could tax momentum as well. (Or as a short-hand, tax fuel and tax vehicles by weight.)

Tax road wear. The weight over each axle to the fourth power times number of axles. That'll put smaller cars on the road.

This is a silly tangential point, but with good design a V8 can be as efficient as an I4 (and with bad design a V6 can be more wasteful than a V8).

Pinning fuel use seems to be the way to go, rather than penalizing engine geometry, for this reason.

It's important to remember, though, that semi-trucks get 5-8 miles to the gallon due to their weight/purpose. Perhaps these new fuel taxes should only affect classes other than A, B, and C to avoid knock-on effects.

>t's important to remember, though, that semi-trucks get 5-8 miles to the gallon due to their weight/purpose. Perhaps these new fuel taxes should only affect classes other than A, B, and C to avoid knock-on effects.

What's interesting here is that semi-trucks cause exponentially more wear and tear on the roads than consumer vehicles, while not paying the corresponding fuel tax — they're being subsidized by everyday drivers.

Also the knock on effects may not be completely negative, it could mean that it isn't economical to drive a truck door-to-door filled with low value merchandise (And give retail a fighting chance).

It's absolutely true that semi-trucks damage the roads.

What I was worried about was trucks used to transport groceries, not delivery trucks.

Last thing the poor need right now is the cost of food going even higher. They're already struggling to get by as it is.

You can tax momentum (and/or weight), too.

Basically, tax fuel and tax the car.

But no need for outright bans. Almost any externality you can think of from (big) cars is finite, and thus a finite tax is appropriate.

it would be interesting to see the effects of taxation in this particular situation in the united states. from what i’ve seen, this is one of those situations where financial penalties do not dissuade or deter proliferation. at a minimum it seems to foment radicalization of political sides toward their general bent (the government is doing too much, or not enough). one side yells louder for more while consuming itself, the other side keeps buying the vehicles out of spite/support (for the manufacturers) as a way of thumbing their noses at the government overreach.

That's the beauty: If the taxes are set right, then people can buy vehicles 'out of spite', and it's all right.

At a high enough tax rate, the would-be gas guzzlers' contribution to the fisc outweighs their probabilistic homicide.