Puranas means historical records, and have been treated such before the british. Interesting to note is that in the name of modern science we have done more damage to our home planet in the last hundred years or so than was done in millions of years before that. As far as rationality is concerned modern day scientists better not speak their mouths about it (e.g. most either do not comment about origin of everything or some believe that everything came out of essentially nothing). They would do good to learn the basics of vedanta that accepts three pramanas viz. pratyaksha (direct perception), anumana (logic etc.) and shabd. Though they try to deal primarily with pratyaksh, they are not aware of the basics of the conditions under which pratyaksha is to be accepted, its limitations etc.
As far as the economy, military benefits are concerned it is mostly a spin by the government -- don't you see that, and if not then get better informed about it from neutral sources.
