Inside the US Command Center at the Front Lines of ISIS Fight

ABC's Martha Raddatz is on the front lines of the fight with ISIS in Iraq.

The command center operates 24 hours a day coordinating coalition airstrikes against ISIS in northern Iraq. It played a key role in the airstrikes that supported the recent Kurdish offensive that retook the town of Sinjar from ISIS fighters.

The officers in the fight there told ABC News the current rules of engagement suffice and that they “have not hurt our ability to strike ISIS,” as one official put it.

A Pentagon official said Monday’s strikes on ISIS oil tankers, transported by civilian drivers, was the first evidence of that shift. Before destroying hundreds of trucks, the coalition dropped flyers warning the drivers to leave their vehicles.

It’s not entirely clear what else the Secretary may have in mind when it comes to changing these rules. Officials at the CJOC said most of the strikes they are conducting are “dynamic,” meaning they are not pre-planned.

As for progress in the overall fight, one senior official there said ISIS, which he believes is operating more and more like a traditional state, is shifting to a defensive stance, initiating less contact and concentrating on protecting its own troops and the population it is controlling.