That's not the point.
Terrorism isn't about making the statement "We can hurt easy targets". It's about the statement "we can hurt any target."
The World Trade Center was a giant building. With control of a plane, it would have been easy to hit. The terrorist aspect is that the hijackers interrupted a regular normal daily routine to commit their chosen atrocity. Now, it's doxing. ISIS is claiming that they have supporters in the US who are willing to kill anyone with a name and an address.
Sure, they've picked a few soldiers now, but the subtext is that their targets could be anyone. A few articles later on the front page, there's discussion of video gamers calling in SWAT raids. 4Chan makes a point of identifying anyone for any reason for the fun of it. Anyone paying enough attention to understand what ISIS is threatening today knows that they could end up a target next week, and it's probably too late to scrub their records from public systems. There is no defense against the doxing, and if ISIS really does have a hidden network of bogeymen in the United States, there's nowhere to hide.
That's the real message ISIS is saying here: You could be next if you piss us off. Bow in fear, praise our particular flavor of deity, surrender all of your free will to our self-interested leader, and so on and so forth.