Apparently fantasising about murdering Margaret Thatcher is guaranteed to raise a titter at Labour & Union gatherings, especially when it's done by a man who enthusiastically praises an organisation that actually did try to murder her.
The thing is I can't imagine anyone making a "joke" like that at a Tory gathering about a leading left wing figure and receiving applause for it, and it was applause McDonnell got not laughter.
Whilst I certainly hope we don't see Mr McDonnell being charged with anything, the fact that such unhinged hatred is so widely accepted on the left is telling. In fact this sort of hatred is so ingrained that they can't see anything wrong with it, so for example Sunny Hundal believes that it is comparable to Daniel Hannan arguing that we should have a different form of health care provision. I don't follow that line of reasoning either. In fairness his response is at least better than the complete silence by the rest of the left.
Not a single Labour leadership rival has condemned him for his remarks either which tells you how they judge the likely reaction within the Labour Party to the sentiments he expressed.