They are encroaching on internet freedom. The bill they want to pass is to force US search engines to censor search results to avoid certian topics and websites.
This is not loving Australia.
A better comparison would have been China, but whatever.
And hacking government websites isn't an effective strategy to "fight back".
If anything, these internet "extremists" just appear to be childishly misbehaving.
And as Narkro said, you dont live under a tyrant.
Your parents get the vote.
Your country can vote against it.
It's at this moment that rallies and petitions help to spread the view on this bill and aid in ensuring it doesn't get passed.
You don't achieve that by hacking into government websites and gaming networks.