As the news networks display maps showing the extent of ISIS’s gains across Iraq, I keep on wondering what it actually means to describe a city as having come under ISIS’s control.

Obviously the central government no longer maintains security forces in these locations, but what kind of a footprint can ISIS actually impose?

Who knows whether the number is accurate, but the most frequently cited estimate is that ISIS has a total of about 10,000 fighters. An intelligence official speaking to CBS News says that these forces are distributed with about 7,000 in Syria and 3,000 in Iraq.

The most recent map from the Institute for the Study of War, shows ISIS in control of Ar Rutbah, Al-Qa’im, Rawa, Sharqat, Anah, Fallujah, Sulaiman Bek, Tikrit, Hawijah, Mosul, and Tal Afar.

A conservative estimate of the combined populations of these cities is 2,878,000 residents.

This would mean that there are approximately 1,000 Iraqi civilians per ISIS fighter. But that number is low, since significant numbers of fighters have been engaged in securing strategic locations — such as the oil refinery at Baiji — as well as manning checkpoints between cities. So maybe there is no more than one ISIS member per 1,500 or even 2,000 people in most of these cities.

For comparison, in New York City there is one police officer per 239 residents, and during the US-led occupation of Iraq, the ratio averaged about one foreign soldier per 200 Iraqis.

I dare say that in much of ISIS-controlled Iraq there are a lot of Iraqis who have yet to even set eyes on any of these infamous fighters.

That isn’t to minimize the threat that ISIS poses, yet its media visibility surely vastly exceeds its visibility on the ground.