In what sense you are talking backwardness. TN and WB are some of the highly literate states and both are highly industrialized states too. Their contribution to nation building cannot be underestimated. By your argument you are saying Gujarat is the only state that has developed and all others are just like some African states. You are wrong. Gujarat has developed because of Gujarati migrations to different parts of the world and sourcing money for its development. Unlike many other states that depend solely on Foreign Investments, Gujarat has double advantage of expat Gujaratis investing as well as some Foreign investments. Go around other states and make comments.
