Full nodes can have their ledger of blocks that they verified. But who is using a non-mining node's ledger to mine on? Miners mine on the last block that is in the blockchain. The only way to get a block into the blockchain is to win the block by mining. If you are not mining you simply cannot vote on what blocks make it into the actual blockchain. The only person who's vote counts is the person who actually mined the block. So even if you have 99% of the hashpower but are so unlucky that you never win a block, you never actually have any say as to what makes it into the blockchain. the only way transactions are confirmed, is if they make it into the actual blockchain. thus the only people who "verify" transactions and actually have authority to enforce their verification, are miners.
What is so difficult to understand here?
Invalid blocks are not in the blockchain. The only way to add a block to the blockchain, is to mine a
valid block. Those who produce invalid blocks never actually have any say as to what makes it into the blockchain.
...I cannot but conclude that ir.hn is maliciously spreading misinformation. I write this post for the benefit of others. I am uninterested in arguing with somebody who is a deliberate liar and/or so manifestly ineducable as to appear braindead.