I completely agree, but at the present time they simply don't have the tools or the where with all to combat them. These groups are bringing things to a pretty terrifying head and we're the ones who are going to lose out. The US gov already ceases objectional websites as per the bidding of the media corps, and hacking has always been a matter of almost all governments national security, but it's not making much of a dent.
They're streets ahead of anyone the government can afford and making statements aimed at trying to scare them is going to get you nothing but grief.
Unless they get sloppy, there is no way whatsoever that they will ever be caught.
What makes you say that? I've little to no idea about the state of the art in what they do, but when I first heard of that low orbit packet cannon software they were using, it was a spectacularly simple bit of kit that made no attempt to hide the source of it's packets.
Now there are ways to do that - faking headers, proxying or running it via a botnet. The former should be controllable at the point of insertion - the ISP level. Granted, there are a lot of those and fixing it'd be a big job, but a firmware update from Cisco ought to be able to block most faked packets. I'm assuming they don't already - having never tried it I can't say.
Taking the second option, proxying large amounts of traffic is a great way to get yourself kicked off a proxy.
A botnet, or a paid for version running on the cloud, always has a weakness - it's control channel. The biggest and most resilient botnets survive by being run from countries which don't care to work with the West to solve these problems, but the impression I get from these hackers from the targets they pick is that they're embedded in the consumer culture of the West, so almost certainly based in Europe or America. The Chinese hackers already seem to have some of the same skills as these groups, and ultimately they're likely to be the biggest threat to the big Western powers (commercial and political)
Anyway, tl;dr. I just reckon that by attacking government targets they're making it more justifiable for those governments to spend the money they need to to fight back. And I don't see any technical reason why they can't.