All of these effects powerfully reinforce regional inequality. Concentration means it is much harder for someone to start a new business that might, for example, try to take advantage of the cheap housing in Minneapolis. Why bother when you know that if you challenge Amazon, they will simply dump your product below cost and drive you out of business? (That is actually illegal, by the way, but the law is no longer enforced.)

Given all this, it’s darkly ironic that conservatives sold their dismantling of anti-monopoly policy as a pro-growth, pro-consumer move. “It used to be federal policy to diffuse economic power throughout the country and ensure every place had access to the market on a free and fair basis. Then, 40 years ago, we decided to dismantle that policy on the basis of an ideology — the ‘Chicago School’ — that held it was economically efficient not to enforce it,” Marshall Steinbaum, the research director at the Roosevelt Institute and lead author of the report, told The Week via e-mail. “Now we’re living with the consequences of subordinating sound policy to that misguided and empirically vacant ideology.”