The simple answer for small repressive governments is to block the HTTPS login form so you have to fall back to HTTP. ATI has complete control of all Internet access in Tunisia. You're just not going to get through them unless you can find a way through.

In some countries I work in we routinely come across censorship and all kinds of dodgy goings on, so we have a variety of tunnelling methods (VPN, SSH, ICMPTX, DNSTX, Tor and a few non-public tunnelling options). For the most part as long as you can terminate a connection in somewhere you're fairly comfortable with you're better off.

Also don't make the mistake of feeling that the US, UK or EU are automatically comfortable options. It all depends what you're doing with the data. A little common sense goes a long way.