For you who believe in the existence of free market monopoly
Here's the real-world remedy we have.
Please read the whole article: it's a wealth of stimulating thought. But here's my favorite part.
In defining a market as narrow as video-rental stores, the FTC excluded online rental services like Netflix and even larger retailers like Walmart. Antitrust requires static markets with a few easily identified competitors. Complexity is too messy for mediocre talents like government attorneys to manage. By defining the market as, say, three firms and only three firms, the regulators can apply simple mathematical tricks to prove the existence of "monopoly power," even if the true marketplace is heterogeneous and incapable of such rigid analysis.