Are you thinking of carbon markets (cap & trade)? Either way, I was always skeptical of cap & trade. IIRC, the economists and environmentalists preferred a st

Are you thinking of carbon markets (cap & trade)? Either way, I was always skeptical of cap & trade. IIRC, the economists and environmentalists preferred a straight up carbon tax. Ideal Pigouvian tax. Trivial to administer. And so forth. As I understand it, while conceptually ideal, its political economy was turrible. It had no constituency which benefitted, so would therefore defend it during the inevitable reaction. Messaging was also tough (eg "if you're explaining, you're losing"). It also lacked strategy and vision. Minimal regulation and "just do it" mandate appeals to neoliberals and libertarians. But doesn't reduce uncertainty for businesses. Further, getting private capital (on its own) to invest in R&D "for the good of all" is unlikely. I think of carbon taxes like "pushing rope". In contrast, IRA is all carrot. Creating plenty of stakeholders to defend its largess. And it establishes clear priorities (domestic mfg, electrification, huge bet on H2). And it uses public investment to attract private capital. As we can all see, IRA (et al) is widely successful, thus far. I personally would have preferred the earlier BBB bill, which had "sticks" to compliment IRA's "carrots". Stuff like performance mandates, which have proved very effective in CA State. Biden Admin is doing what it can thru executive action to move the needle. Fingers crossed.