What kind of bug is this?

It looks to me like the winged form of termites that emerge once a year to spread and create new colonies, but it could be a winged ant. Termites have: (a) straight antennae; (b) two pairs of wings about the same size; (c) long abdomen more or less uniform in width. Flying ants have: (a) bent/crooked antennae; (b) one pair of wings markedly larger than other pair; (c) "pinched" abdomen "pinched" like a wasp's waist.