Well technically children don't have to suffer for the content to be produced, it is theoretically possible (although so unlikely that is pretty nearly is impossible) for the same exact image to be produced by the flip of a coin and random chance. So there is not MUST technically. Also children already suffered for CP to be produced. More children don't NEED to suffer for people to view CP, it is just an unfortunate circumstance that they do. And you are not going to unmolest previously molested children. PIR is private information retrieval, it is a cryptographic technique that allows somebody to obtain an item from a database with no third party (including the host of the database) being able to determine which item they got out of the database. If people only downloaded CP from PIR networks there would be no ability for anybody to claim that demand leads to supply, since demand cannot be determined. Therefore I ask you, are you okay with pedophiles downloading CP from PIR networks that operate without making a profit?