My dog tries so hard to make friends (Sorry buddy)

Do any of you have cats AND dogs? Do they fight? Do they get along?

My dog Louie absolutely LOVES my cats. (And my parent’s cats..) He tries so hard to cuddle with them, give them kisses, and play – he’ll bring a toy of his to them and drop it, begging for friendship. He’ll even drag their favorite toy (a string) around the house in hopes that they will chase it like they do when it’s me dragging the string.

But it never works.
They hate him. Absolutely, deeply DESPISE him. They’ll hiss and run away, leaving Louie looking so devastated. And hey – they are awesome cats. They’re loving to me and playful. But why do they hate the darn dog so much? It’s not like he chases them or barks at them! (Which is weird/great for a dog!)

For those of you who do have animals that get along – what did you do? Any advice? Or is it just the natural way of ‘species relations’? The only thing I can think of besides ‘it’s natural’ is that I have went from giving them all my attention to giving the dog most of it… Jealousy is a green eyed monster!

WHY CAN’T WE ALL GET ALONG!? I’m thinking Homeward Bound kind of love.