I need help, a friend has asked me about the possibility of censoring Bitcoin by blocking transactions on the internet (as some websites or internet content are blocked in some countries). And I am not sure if a transaction that you make can be blocked before it reaches a node (miner). Or if it is totally impossible for something like this to happen. In the original paper and other articles, they talk about the "transmission of new transactions to all nodes". Is this transmission made over the internet? And being that so, could it be possible to censor that transacction that goes through the internet the same way governments blocked access in some countries to certain websites? (We discard other options that we know exist such as sending btc transactions by radio and the like)

Thanks in advance.