It has, as has the coverage glorifying it and fueling these clowns to keep going. An overwhelming majority of "hacktivist" work is exposing whatever private info they can about a person or group that they hear did something wrong in the news, it accomplishes nothing almost literally every single time it is done and cheapens the efforts of true, coordinated activists.
Internet activism has its place in the world. Without a proper system of checks and balances from society, many governments and/or corporations would run freely in their immoral acts. With that having been said, internet activism these days often goes too far. It is one thing to disagree with a government policy, it is another to hack a database and publish the personal information of employees that work at said agency.
Every day, denizens of the Internet are assaulted by oppressive censorship laws. I wouldn't take things to the same level as Warmonkey, but the debate is a serious one, and the denizens have the right to defend themselves and their culture, I'm not talking about "real life" sites like Facebook, I'm talking about sites with independent cultures, ie. 4chan and reddit. If powerful countries are able to pass enough restrictive laws, many of the glorious internet-based cultures will die, and an entire society full of ideas will have been lost.
No, it has not. This country has always had extremist elements and with every new communication technology invented these extremists will use it. From the printing press to radio to film and television and now the internet; extremists have always used these mediums to spread their message. We live in a country that provides free speech, and this includes extremists and their opinions. Plus, extremism is always changing. During Word War I one could get arrested for reading the Bill of Rights aloud on a street corner because the government deemed it could incite riots.
The fact that there is still censorship in the US and around the world is showing enough that internet activism needs to become more extreme. The internet is a sovereign dimension and countries everywhere have violated its territory, i.e. declared war. There has not been enough retaliation and I believe countries' economies or infrastructure should become a target unless they remove themselves from a sovereign entity. It's a war, and regardless of a war being on the net or in real life, people are going to get hurt.