Will lots of love and attention solve this?

I just brought home a newly neutered, 55-pound 1.5 year old Afghan-hound mix. When he's out in the open living room, he barely knows what to do with himself. He turns in circles or else glues himself to my side. He only lays down for some much needed sleep after neutering when he's in his crate. He probably spent most of his life in a cage.

When outside, everything scares him: cars, the train overhead (we live in a densely urban part of Chicago)... understandably so. He came from a shelter in the south and likely was some kind of farm or suburban dog before that.

Will lots of love and attention build his confidence? What else can I do? My heart is absolutely breaking when I see that he doesn't even know how to handle having a little free space. He's already piddled on the floor either because it's a submissive gesture (or maybe he had to go really bad -- he was WAY too scared to potty outside with all the noise).

I already love my big buddy and I just want him to feel happy and safe. Any advice is appreciated.