Carbon taxes are typically used for every other purpose except to "save the earth".  Providing politically connected rent seekers with free money.  Enriching green "entrepreneurs" as they peddle impractical schemes with no value proposition.  Providing a virtuous "cover" for a big new tax that will induce the gullible to give up their wallets.  The list is lengthy.
Being used as a weapon in a trade war is a new one for sure.