>If you cut any industry finely enough, you will find a monopoly

And inversely, if you cut any industry coarsely enough, you will never find any monopolies.

"Don't break us up! Sure, we may own the entire telephone service, but we do not have a monopoly. See, you should be looking at total human communications. People talk in person, send letters, etc. We own a teeny tiny slice of total human communications."

"Don't break us up! Sure, we may own the entire rail network, but we do not have a monopoly. See, you should be looking at entire human travel. People walk, ride horses, travel by ships, etc. We own a teeny tiny slice of total travel industry."