Comments on blog posts are reviewed and approved here.
Nothing publishes itself
Every comment is recorded as pending. It does not appear on the site until you approve it.
So your silence is not publication: unreviewed comments stay invisible rather than going live after a while.
Four states
Pending has not been looked at. Approved is on the site. Rejected means you looked and will not publish it. Spam is kept apart.
The difference between rejected and spam is for you, not for visitors — neither is ever shown.
Only signed-in customers can comment
Anonymous comments are not possible; every comment belongs to a customer account. Which means "who wrote this" always has a clear answer.
Replies hang off their parent
Comments can reply to each other. Deleting one leaves the replies beneath it without a parent — look at the replies before deleting.