Q: iPhone or IPad isn't acknowledged by MacBook Pro

I plug my iPhone and iPad into USB ports on my MacBook Pro (mid-2015 10.11.6) and nothing happens. They don't show in Finder and they don't show up on iTunes. The iPhones are a 6s and 6s Plus, both running 9.3.4. I don't recall right off the age of iPad but it is running 9.3.4. I have turned all off and back on. I have tried 6 different cords. Both USB ports appear to be working since one is normally attached to Time Machine and I can pull newly made and backed up files. The other USB port also appears to work since it has the hub that runs my mouse and keyboard and printer with no problem. I disconnected the hub on this side and it was running the only the iPhone or iPad when I was using it. Suggestions for what is next?