The Northern Mockingbird is a strong bird with a great ability to imitate other bird’s songs and calls.
I admire them not for that ability so much as for being bold and protective of what they perceive as their possessions.
The Northern Mockingbird usually establishes a territory and everything that is contained within a determined radius they are to protect and keep safe. I always name them as the “guardians”. I’ve seen them chase birds larger than themselves if they got in their territory.
Usually they perch on a high point such a high tree top, pole, roof top etc. From that point they keep an eye on what’s going on in his zone. I suspect that they are the ones that set the alarm when a Hawk is lurking around too close.