How long does it take for search engines to realise a page isn't there?

It depends. Search engine will visit certain site more frequently than others (depending on how frequently that site is updated). As a rough rule of thumb, search engine should be able to re-index the entire web within one month.

But they usually can detect the change much sooner. To test, all you have to do is to perform a search for a few sentences in your deleted article.

Definitely it depends on the updating frequency, which is a considerable factor of the frequency the robots crawl your site.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.