CORRECTION: I misidentified this insect. After writing the article I posted these images on iNaturalist and someone suggested it is Virginia Flower Fly (Milesia virginiensis) rather than Sphecius speciosus (eastern cicada killer). Within a few hours two others on iNaturalist agreed this is Virginia Flower Fly (Milesia virginiensis).
So all the interesting details do not apply to the insect in the photographs, except of course for when and where I spotted this creature.
When I first spotted this insect this afternoon I thought it was a yellowjacket. But as I approached closer I saw it was huge, about 1.5 inches long. Actually I had seen one of these odd insects along the driveway near the front porch on July 6 but did not get a good photograph that day.
I believe it is Sphecius speciosus (eastern cicada killer), a solitary wasp common in Eastern United States. Because of the size I think this is a female.
Cicada killers are not particularly aggressive to humans but they sting and paralyze cicadas before carrying them back to the nest. The female lays an egg on the cicada, which will become food for the larva when the egg hatches in a couple of days.
Interestingly the mother cicada killer anticipates the sex of the egg and provisions the nest with one cicada for male offspring, two or three for female offspring.