That's definitely part of it. But the flip side of that is that as the U.S. tightens emissions, production outsources elsewhere, possibly where emissions standards and many other environmental standards are much lower, which could lead to an overall net harm.

Thus if you have 3 countries, it may be worse for just one of the countries to pass environmental constraints on the production of tradeables. Either all three countries do it, or none do it, or you don't trade at all with those that don't do it.

Why people don't take these arguments to their logical conclusion is beyond me.

A label would help. It transfers the responsibility to the consumer.

If you have a dozen of regular eggs, a dozen of cage-free eggs, and a dozen of pasture-raised eggs... If you pick the regular choice you know you are contributing to less humane conditions for chickens. Now it is your choice.

To a point - if you're going to have labeling you'll already need some kind of regulation and enforcement. Seems to me like if you're going to set that up, you could just turn the knobs a little farther and make the 'bad' choices cost 20% more than the 'good', for example.

Adding a tariff to goods has three drawbacks

1. very easy to cheat. E.g. during Trump's tariffs on China, there was mass cheating as goods were imported into Vietnam, relabelled as made in Vietnam, and exported to the U.S. When there is big money at stake, the incentive to cheat goes way up. Trying to audit every exporter's Asian supply chain in search of Chinese inputs is tough.

2. Imposing a country-wide tariff does not incentivize any producer to adopt more efficient processes. Imagine if the EU decided the US gas taxes were too low, and so they slapped a tariff on American cars. Would that incentivize Americans to use less gas? Would it make Americans favor an increase in gas taxes?

3. They lead to retaliatory tariffs by the other side. There's no such thing as pure one way punishment, no matter how justified you think you are. The other side will punish you by the same amount, if they can, in order to punish what they view as your bad behavior in trying to punish them.

Now I'm a big fan of trade reductions, but that's because it's part of my personal war on globalism. But make sure you are signing up for the same mass trade restrictions - e.g. blanket bans on certain products coming from all of East Asia - because that's what this is. Don't think you can wage a war against CO2 without also waging a war against globalism. International conferences are fun, but they have no teeth and don't get the job done.

I don't disagree about encouraging onshoring for example (much easier to make those regulations stick that way). But I was mostly responding to the parent's idea that shifting the burden/choice to the consumer was a positive thing. My instinct is that, if we're talking about humane treatment of chickens, it would be best to impose regulations so that all the eggs met a minimum requirement - so consumers couldn't "choose wrong". But of course that makes them all cost more...

Yes, I know the point you were making and it's a fair one. I was just elaborating. It's unfortunate that your post was downvoted, there is nothing wrong with it, IMO. I was taking this as a discussion.