I bet he'd find that they "delete" even non-political things. The obvious answer is that a search engine's job is to give what you're looking for in the top few pages, not to give an exhaustive list of thousands of pages. Unfortunately this means that it will cater to the common user, not people with specialized needs. I remember years back Google put their old database online for searching, and you could find all sorts of useful technical things that were normally buried in search results.