I was merrily reading queries this morning, and came upon one that Zinged! my interest. I slowed down, read more carefully. Wow, this is interesting! It's about an event I've never heard of, that sounds like it could be a really interesting book of narrative non-fiction. I've got my eye peeled for good narrative non-fiction these days.
Then suddenly...splat. The query isn't for non-fiction. It's for a novel. I'm so disappointed I want to write back to the querier and say "write about that event!!" But I don't.
The foot shot is this: when you open a query with information that IS NOT IN YOUR BOOK you run the very real risk of splat! You don't want me too disappointed about what your book is NOT to read your query.
I can't say this often enough: your query is about YOUR book. Tell me who the characters are and what choices they face. If there's a real world event that has an impact on your book, tell me about it in the context of your book--in other words LATER not sooner in the query.