I like to take the backdoor argument to its logical conclusion - if we're not going to allow terrorists to hide by encryption, why should we allow them to hide by speaking in private? It's about time construction companies and car manufacturers stopped giving terrorists a place to hide - make always-on microphones mandatory in all homes and cars. Don't worry - they'll need a warrant to access the recordings!
Government homes and offices are special. The general public is not allowed to know what goes on behind their doors.
Seriously, don't give the government ideas :( I am of the opinion that our current PM would gladly shove cameras up people's *sses if she thought it could catch terrorists.