You’re all IT types, and so familiar with the OSI Model of networking, which divides networking into seven layers, starting with Layer 1, copper wire and such, and up to Layer 7, where applications live. Websites live on this top layer but depend on all the supporting layers.
These days, access to information pretty much *is* freedom.
It’s not necessarily easy to take away your freedom at Layer 1, because it’s hard to cut every wire or terminate every wireless signal, though it could be done.
People easily can take your freedom by cutting off Layer 2, the Data Link layer that actually pushes packets. The regime in Egypt tried that, cutting ISP connections and wireless telephony. People found ways around that, including dialing in to remote services, and rebuilding wireless service by smuggling in equipment.
Federal administrations have been preoccupied with an “Internet Kill Switch,” which would basically turn off DNS or perhaps routing, taking your freedom at Layer 3. Fortunately many people recognize that doing such a thing would certainly kill lots and lots of people. Many hospitals, for instance, use GE’s Cerner medical records systems. All their data is in a remote data center. If the Internet is “killed,” so will be quite a few patients. Just for a single example. Certainly you can think of more.
A Denial of Service (DOS) attack actually could hack any layer of a particular website’s networking. But typically these are Layer 7 (Application Layer) attacks, in which one application (say, LOIC) launches nefarious activity toward another application, say Russian protester websites.
Not that I can imagine any regimes famous for heavy-handed suppression of dissenting speech. Instead, let me direct you to the ever-interesting Naked Security website:
http://nakedsecurity.sophos.com/2011/12/05/russian-election-cyber-attack-brings-down-websites