This, and related ones such as “Could the Web have been built on FTP?”, or even “Why did the Web win, and not Gopher?”, are excellent questions with really interesting answers that expose historical, political, and technical aspects of the World Wide Web project. I don’t pretend to have all the answers, but I’ve done my research, so I think I’m a good person to ask (of course, you could just ask Tim for the authoritative answer)
I think the answer to Daniel’s question is pretty easy; Tim chose to start with a new protocol, because he was innovating and FTP was well-entrenched at that time (if he even considered FTP at all, I don’t know). Tim’s (and later, Roy’s) innovations would have required substantial changes to FTP too (support for URIs, and the fallout from that being the big one), so I think it was a wise choice.
So, could the Web have been built on FTP? I’d say probably not, no. Other than the aforementioned points, other things that would effect this would include;
- FTP uses two network round trips for each retrieval, due to first-pass negotiation
- FTP has no redirection capabilities
- FTP doesn’t have a POST method
- FTP implementations don’t permit delegation to plugged-in software
There’s probably more issues. Add those to the fact that FTP was RFCd in 1985, eight or nine years before Web standardization began, and there’d be a lot of pushback from the IESG to changing FTP into something that it wasn’t intended to be. And rightly so.