Why Are There No Big Cities with Municipal Broadband Networks?

So asks the Atlantic:

The Institute for Local Self-Reliance recently compiled this map of all the communities in the country that control their own access to the Internet. At best count, there are about 340 of them with publicly owned fiber-optic or cable networks, serving either all or parts of town. In these places, those residents and businesses served don’t have to spar with telecom giants like AT&T and Comcast. They get their Internet instead – like many communities do their electric utility – straight from the city.