In general you can vote to close every question which you find inappropriate. It needs votes from other Tor.SE users to really close it. If there are none, the question will stay open.

Regarding your question I would agree on the first question. It seems too broad for me. However especially you should always comment on the question when you want to close it. This will help the user to create a better question next time or to rephrase the current one.

When it comes to [my questions][1] I'm obviously against a vote to close. :-)
While the general question is obvious, there is a nuance which might be interesting. From my knowledge DDoSing DAs will not bring the network down immediately. As far as I know existing connections will stay and clients will also use informations from other Tor relays. I was expecting an answer along those lines.


  [1]: http://tor.stackexchange.com/questions/196/would-distributed-denial-of-service-ddos-attacks-on-the-directory-authorities