> To mine bitcoin you need to buy an asic, which is a single purpose physical good with at most two original maker (fabs). It needs to be physically received. T

> To mine bitcoin you need to buy an asic, which is a single purpose physical good with at most two original maker (fabs). It needs to be physically received. This single distribution is trivial to track by the authorities and makes bitcoin mining a permissioned system. There is no hard limit here on the supply chains for miners, this is like saying "there are at most two mobile phone operating systems". Sure it is somewhat true, but there is no deep reason it must be true. Second, bitcoin mining is not a permissioned system. A permissioned system means that the system itself imposes permissions. You are talking about actions outside of the system that would perhaps incentives people to not use the system. This is a concern but not the same as being a permissioned system. > All it takes is indirect or direct control over >50% of hashrate to censor anything. For bitcoin PoW and ethereum PoS (hashrate => stake percentage) this is true. However the difference is that with PoW it is possible to increase the supply of mining hashrate to overthrow this quorum of censorship by literally building more physical hardware. In ethereum, if this ever happens there is no recourse as the supply of coins to stake is finite.