You can't reason with an animal the same way you can with a human, and this creates two problems: it's hard to figure out why the cat is scared, and it's hard to explain to the cat that it shouldn't be scared.
Why is the cat is scared?
That's hard to answer. It's possible that your cat has always been scared since birth. It's also possible that this is due to an past experience which has left a scar.
He loves to play lazer. We may be able to touch his nose.
This is actually quite good. Playing means that your cat isn't paralyzed with fear, as that would mean it's unable to relax and play.
Touching his nose is also quite good. The nose is a quite sensitive area and if he lets you touch it (even if it is because he's sniffing you), that means he doesn't fear you're going to hurt him
We cannot pet him. He runs and hides when we are about sometimes.
Given that you can touch his nose but cannot pet him, this strongly suggests that the cat is unusually caught up on being pet. This may be a past emotional scar that the cat is unable to get over.
For example, two of our cats were rescues that were caught from the wild, and we adopted them a few months later. Years down the line, with the cats turning from shy cats to loving pets, one of them still refuses to let us touch her belly (we suspect she holds a grudge after having been sterilized, but it's just a guess).
That is her hard line. She will come for love in many forms, but trying to touch her belly will end the affection and she will walk away. There's nothing you can do about that (directly), you can't (or shouldn't) force your cat to do something against its will.
How to tell your cat it shouldn't be scared?
This is much harder than it is for humans. You can't talk to a cat, or convey information, all you can do is ensure that the cat feels safe and protected in your house and around you.
This comes in many shapes and forms: don't startle the cat, make sure they have private spaces if they don't want people around, build a relationship of trust, ... Just be a loving pet owner and don't give the cat any reason to mistrust you.
That being said, there is no surefire way to guarantee that your cat is ever going to like being pet. Some emotional scars may never heal.
If your cat will never be happy letting you pet him; evaluate your options: do you want to pet your cat, or do you want your cat to be happy? I hope you choose the latter.