My node protects me. It does not protect the network. It does not protect you.
Your node protects you.
Proof-of-work is what determines what my node will determine to be true. PoW is what eliminates a conflicting signal such that my node (and all nodes) can independently verify which transactions remain unspent (at least, those with a certain number of confirmations -- e.g., 6 confirmations).
Yes, there seems to be a misconception that nodes vote on the rules. Fortunately, Bitcoin does not have governance.
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