You really can’t get someone more left-wing on the American political spectrum than Ralph Nader – that is, without going to communism or Marxism.
And yet here he is below giving us a badly-needed left-wing perspective on why open borders and mass immigration are a bad idea. And he is perfectly right too. I put forward a similar case here.
Yet another thing to add is this: with open borders, Keynesian fiscal policy and policies to create full employment are badly thwarted and disrupted, because as your economy booms your open borders just allow more people to flood in and create more unemployed and more competition for jobs.