Or just have each protocol do what it's supposed to, rather than redirecting one to another? In general, aren't advanced users supposed to like having the option to make their own decisions?
However, after the first visit, your browser learns through HSTS (the Strict-Transport-Security header) that accessing news.ycombinator.com without TLS is not supported, and won't attempt to access it again except via TLS. (For a year, in HN's case - this is configurable by the site administrator.)