If we follow the idea of killing everything that's "insecure" then we will end up killing everything, because nothing is 100% secure. I vote for improving JavaScript, for example, by sourcing external code via Google Caja. We should also improve defense against XSS and CSRF attacks in today's most popular frameworks (because, a lot of the times it's not the JavaScript that's insecure, but the frameworks that developers use - - i.e. making it possible to source arbitrary HTML is a very bad idea, no matter if JavaScript is used or not [e.g. one can do malicious attacks via an image tag as well]).