In the ads.twitter.com UI, location targeting appears to be required. The field is titled “Select locations (required)”, and the field highlights red when it is not input. But I can still save the campaign, and even set it as running. And through the API, I can create campaigns with no location targeting.
This seems like a bug in the ads.twitter.com UI. I should be able to target based on any of the targeting attributes without necessarily entering a location, and, in fact, that’s critical to my use case. If this is just a UI bug, then there are few consequences for me, but if I’m missing something about how targeting works, I’d like to know what that is.