What are you supposed to do once your at the zenith tech hub on puzzles and survival?

The hub is only available for use during wasteland wars. Newer players sometimes confuse this as a campaign directive though.

When you have zenith/wasteland wars, your state must defend the hub from opposing states commandeering it so it is imperative to have a very strong hub. Towers need strong captains as well, if a opposing state takes a tower it will fire upon the hub and injure those within. Wasteland war is won by whomever occupies the hub the longest. Opposing states can take the hub & reset the timer, this can go on for the full 24 hours, hence why you want a very strong hub to prevent that