... of the former Soviet Union, the mighty kremvax rises ...

"We did not do anything illegal"

So the Russian government has stated that there is nothing illegal in anyone hammering the Russian government's sites and crashing them, and that they would have nothing to complain about if this happened.

And what prompted this electronic attack? How did Estonia "act illegally" towards Russia, eliciting its electronic fury?

It elected to move a statue depicting Soviet soldiers from one place in Tallinn to another.

The attack was in fact a lot bigger than "100MB", the sites did not 'respond' because at first the some parts of connection with russia was almost closed down and then attacked networks to the rest of the world (large amount of botnet attacks came from infected US PC's). The scale of attacks was quite big and well coordinated. Local network guys did great work and online banking worked inside Estonia most of the time. There is no way it was done just few 'russian patriots', but there was a lot of web pages teaching regular russians how to 'join in'.

So some think that I should have used some botnet army to retaliate ? Break laws and make even more networks flooded ? How would any of that make anything better ? If monkey starts throwing shit at you, you will not start throwing shit back. That's the difference between monkeys and humans.

What would actually be lost by a combined decision to switch Russia off the internet? I'm woefully unfamiliar with the practicalities but it seems like something that would be doable by automatically denying any traffic with a Russian IP.

They could use their infrastructure to fire spam email and viruses amongst themselves while everyone else got on with actually doing stuff (or, in my case, slacking off).

Don't attack, just ex-communicate. All we have to do is cut all traffic Monday to Friday until they effectively outlaw DoS and the spam gangs. It will damage them more than us. And they can't DoS except at the weekend which is a decent protection and justification anyway.