Lily Lily Silly Billy,
The statement that Socialism eventually runs out of money and is unsustainable, (ProgLibs LOVE that word!), whether or not that statement has any merit, has nothing to do with Thatcher's political popularity or her opinion of Pinochet. You are attempting to link the arguer's personal characteristics to how factual the subject's statement is. That is ad hominem.
I suppose if a ax murderer wrote that 1 plus 1 = 2, you would deny it based on their character.
Finally, if you take Socialist or Communist philosophies and line them up and compare them to Progressive Liberal philosophy, (I assume to be your camp), as well as Classical Liberal philosophy, (Me!), how do you really think they would match up? That's all I was saying, but you love to read more into things than are really there. Focus dear, focus.