How do you destroy a tech monopoly?

Monopolies are on everyone's mind right now, specifically tech monopolies - from the DOJ antitrust suit against Google to the ongoing European investigation against Google for anticompetitive behaviour, as well as the national investigations from Italy into Google and Germany into Amazon. Monopolies are not new, but at this scale and in this space they certainly look a little different. And so the questions we need to ask ourselves, the way we define the markets and the regulation needed all need to be a little different.