BLACK AND WHITE CHECKERED FLOOR

He is a different dog when he's out in public. His ears turn beet red, the skin under the very short fur that covers his skull is the same red color. He sucks in his stomach and chest, his bones stick out, his tail is tucked between his legs, he trembles and stares wide-eyed with abject fear. He might take treats, he might not, when he is the essence of a "chow hound".
It's like he's just waiting, biding his time until he's proven right--someone is just going to haul off and beat him to a pulp. That's how he acts...like the whole world is against him...
When usually people are in awe of him. Some are terrified. Most are reverent. People elbow each other and point and stare, mouths hanging open. "Look at that dog!" they whisper loudly.
He's never really had a bad experience when out in public. Pet store employees adore him and ply him with treats. And yet he sits with his shoulders down, ears back, head hanging, like they're whipping him with chains rather than giving him food and telling him how wonderful he is. Doesn't he feel any of that positive energy? Doesn't he feel how proud I am of him?
It was a concerted effort to settle my own nerves, to remain calm, to channel that through the leash. He will take treats from me, he will do all sorts of tricks/commands, he will even lay down on the cold tile floor while dogs and people walk by. And yet he still acts like he would rather hide somewhere, anywhere but where people can see him. Like he's ashamed of himself, of his breed, of the things he knows some ignorant people feel towards him.
He is ungodly sensitive.
And yet at home...he is the sweetness. He is my boy. My overly affectionate, boisterous loud mouth terrorist. Trouble is his favorite past time. He is full of bravado but completely submissive to me. Why can't I get him to trust me when we're in the pet store? Enough to just...relax. I don't care if he ever gets along with strange dogs or strangers, but can't he just accept them as they walk by? To not look as if he expects to get kicked and beaten at any given moment?
It tears me up inside. Wondering how to fix it. What is it that even needs to be fixed? It just can't be healthy for him to be so completely afraid and uncomfortable....

Hear, O Israel: The LORD our God, the LORD is one. Love the LORD your God with all your heart and with all your soul and with all your strength. These commandments that I give you today are to be upon your hearts. Impress them on your children. Talk about them when you sit at home and when you walk along the road, when you lie down and when you get up. Tie them as symbols on your hands and bind them on your foreheads. Write them on the doorframes of your houses and on your gates. - Deuteronomy 6:4-9, The Shema Prayer

It's the floor at Lula. It's pretty. That's about it. It's enough.