Sounds like the bomber didn’t want to kill anyone else besides themselves.
I dunno, I got a different impression. Some of this is just speculation, but there was a timer set to 15 min and it went off, from what I understand, before the 15 min expired. There was a message being played from the RV before it happened. Of a woman repeating,"All buildings in this area must be evacuated now. If you can hear this message, evacuate now.". I can only speculate on their motives, but either they didn't want to hurt anyone or it could have been a way to lure people out for the explosion.
The cops responded to the scene and were evacuating people but telling them to leave through the back of their buildings. One of the officers was thrown to the ground from the explosion.
Their target though seemed to be the AT&T building. In California, for example, there is a joint AT&T and NSA building which is blurred on google maps. The Nashville one is also blurred out. Though I'm not sure if this means that the building also is government related. Or if the culprit was trying to distact people or test the response of severing communications like that.
This is a link related to the NSA's "Room 641A" which is the one in California. AT&T was holding a server that was dedicated to their operations.
Room 641A - Wikipedia
I do think though that it sounds like they were trying to at least lure the police in. What with the gunshots before. I just don't know if that was all there was to it. And I somehow doubt this is the last one we'll see.
This channel on youtube has been covering the event and had some thoughts on it like I did: