A walk around a backyard can show plenty of predators, even without hawks or large mammals around. It just means looking down at the flowers or ground for invertebrates instead of up. The wasp above appears to be in genus Isodontia, probably I. apicalis or I. mexicana.
Despite their fearsome appearance (and more fearsome stingers), wasps are useful to have around. Most wasps and hornets prey on other insects and help control garden pests. Wasps in genus Isodontia have been recorded preying on tree crickets and related insects, many of which feed on leaves and fruit. Wasps also assist in pollination (though not to the same extent as bees), like this wasp is doing.
Another insect predator was this robber fly (possibly Efferia aestuans or a related species). I am not sure what its prey is.
This crab spider was lurking in plain sight on top of a flower. Crab spiders have a remarkable ability to blend into their surroundings so that they can strike when an unwary insect comes close. Because of their stealthy approach, crab spiders sometimes take prey much larger than themselves.