There is no need to "force" HTTPS for a site. The site can do it by itself.
E.g., try going to http://www.bankofamerica.com/. That's an insecure link. But before you know it, you will be looking at their HTTPS site. Initially, you will be connected to their insecure site, but it will quickly redirect to their secure site.
Think about it: if a bank depended on customers to type HTTPS, problems would develop instantly.