Gosh, I dunno.
What if there were some way of replacing those currently in power according to the will of the people they are supposed to serve? Perhaps people could indicate their choice of representative in a secret ballot, and the one with the most 'votes' gets 'elected'?
Anyone think this is an idea with legs?
Look, liberals do not stiffle debates about immigration, violence on tv or any of the other subjects mentioned.
What does happen is that when the discussion moves from being a rational, fact-based discussion into an emotion-based rant based on what some bloke down the pub said (aka 'Minterism' or 'AOG-ism'), it inevitably decends into farce.
Arguments that start 'I'm not an [insert bigotry here], but [insert assertation that proves person is exactly the type of bigot described in the first clause]' are never going to produce productive discussions. If immigration discussions become an opportunity for people to chip in with their own quite clearly racist tales of 'the blacks' or 'the asians' or 'the asylum seekers', of course they're going to get called names.
Occasionally, a sensible discussion does break out on here, but sadly it normally gets hijacked.