Before he crowded the black guy and pushed with his chest, the black guy pushed him with his hands. Then he walked close to him and dared him to push him again, and then he was crowding him and pushing with his chest, and the black guy put his hands in the air and tried to deescalate. Watch the video from the beginning, and you’ll see.
The video begins with the white man already standing too close to the black man. Remember, that is the black man’s front door.
Then (watch his feet) the white man takes a step even closer toward the black man, who instinctively pushes him back and takes a step back himself.
I’m only using the terms “white” and “black” to describe them in a quick way. We could say “man in the green shirt” and “man in the white shirt.” All that matters is, one guy went to the other guy’s front door, argued with him, got up real close to him, and called him names.
There appears to be a back story. Then again, other neighbors claim this guy harasses everyone. But, let’s wait and see which back stories are true. As is, for now, we can only judge what we see in that video.