I'm curious about this, how would disconnecting the internet cost a state too much?
Countries bring in a lot of money from companies trading on the Internet.
One of the key conclusions of the BCG report is the estimate that, in 2009, the internet business made £100 billion in the UK. That is 7.2 % of the 2009 GDP.
http://www.guardian.co.uk/global/datablog/2010/oct/27/data-store-economicgrowthApart from this, to effectively disable the Internet for an entire country you'd also have to disable international telephone calls.