Paper Wasp? in Kingman AZ USA

Indeed, a species of Polistes.

Any typical over-the-counter wasp spray will be very effective on these. Their nests are open air and made of paper with a honeycomb look. Usually located in eaves or along structural beams. Quite easy to spot.

These tend to be rather benign creatures unlike their much more temperamental relatives (the yellow jackets and hornets). However, when a nest becomes about the size of (the palm of your hand) these can then be of concern because anything walking underneath them may be perceived as a threat.

So, look in your attic to see if they have found a way in and spray the nest that you see (no matter the size). Most wasp sprays shoot up to 20 ft for your own safety.

Then look to see how it is they found their way into your attic and try to seal that up to prevent a reoccurrence.