It's hard to say what the net effect is. It's true that such attacks give the government an effective, if fallacious, argument: "we cannot give in to blackmail"

It's hard to say what the net effect is. It's true that such attacks give the government an effective, if fallacious, argument: "we cannot give in to blackmail". On the other hand, large-scale media coverage started only after the Anonymous hacked the government websites. Before the attacks, the Polish media were not interested in ACTA. This in turn helped mobilize politicians from opposition parties and, I think, also the protesters.