> The majority argued that Congress could ban local marijuana use because it was part of such a "class of activities": the national marijuana market. Local use affected supply and demand in the national marijuana market, making the regulation of intrastate use "essential" to regulating the drug's national market.
https://www.oyez.org/cases/2004/03-1454
> The majority argued that Congress could ban local marijuana use because it was part of such a "class of activities": the national marijuana market. Local use affected supply and demand in the national marijuana market, making the regulation of intrastate use "essential" to regulating the drug's national market.