How to stop this level of paranoia?

I know that old pessimists have always been with us:  I remember a neighbour when I was a kid once  chatting to my father about how everything was dire and the world (and country) were getting worse and worse.  Mind you, this might have been in about the late 60's, when there was a considerable amount of bad news on the TV: Vietnam, the sexual revolution and doubts about capitalism's ability to thrive without environmental disaster were all key themes.  Not to mention what was going on in China and Russia and the possibility of nuclear war. 

But as a kid I was inherently optimistic (I suppose techno optimist, given my interest in science in the space program), and so it seemed to me that the neighbour was a sad case.  And, to his credit, my father thought so too.   "He's always thought everything was bad and getting worse. Some people are just like that." was his observation once the neighbour had gone back into his house.  (Well, I think that's a pretty close recollection.)  

Today, the problem of pessimism is exacerbated by online communities where the paranoid and conspiracy minded find it easier than ever to form a mutual support network.   You might think that this is harmless in some ways - keeping a small community of sad sacks in their own little world - but  the problem is, it surely works to deepen their paranoia and pessimism, and probably to bring others into the fold as well. 

Take this recent, fairly typical comment from (what I assume is) some older bloke in Queensland:

This comment comes in a Steve Kates thread about how "socialism kills".   The American "hard Right" started this "any policy involving any government intervention in anything is socialism" nonsense, and Steve Kates, a political idiot, sucks it all up and passes it on the blog of the (marginally) more sensible Sinclair Davidson.  

Then, in a post in which Keryn Phelps' Labor-like environment/refugee policy positions are listed he notes "These people are your enemy."   What uncivil and paranoid talk for an Australian.  

Basically, in their mind, centrism has become "socialism" - and all part of an evil plot involving culture, schools and political plotting many decades in the making. 

It's hard to say how influential or widespread such thinking really is - I mean, I can't even tell how much it is hurting the Liberals internally, given that so many at Catallaxy say they are abandoning the Party for the likes of Australian Conservatives, and will not vote for the Coalition in the next election.  (Or so they say - of course I don't believe that all that many will follow through, and in any event, their preferences will still go to the Coalition candidate.)  

But to the extent that there are "hard Right" members who really do want the Party to reject climate change action, privatise the ABC, and go all the way with whatever Trump thinks, it surely is hurting it internally.

The paranoia needs to stop and be wound back - but how?

I think a real problem is that no one within the Liberals is prepared to call it out.  They still linger on in the hope a "broad church" approach can work, when it is very clear it cannot.  

Malcolm Turnbull, you are now free to speak your mind - save your party by talking out about this.