Well mine are civil with civil dogs but will be assertive with dogs that are pushy or rude, so considering the vast majority of peoples pet dogs are both of the latter and as another arbitrary member of the "its your fault even if your dogs didn't start it" club, leashed in public always.

in the UK it is illegal to have your pet straying off leash away from you. We can let dogs off leash in parks, woods etc but under supervision. If a dog is found straying, then it is taken by a dog warden and placed in a pound until owners come forwards to claim, or a microchip is found.

I would have thought that you would have to be careful with letting your dog roam free, in this day and age people are being sued left right and centre. What if your dog damages something, or manages to cause an accident and somebody gets hurt.

If you want something you can just let out the door, and let roam free - perhaps a cat would be ideal

Can't agree here. I supervise my cat, too. Cats, some cats will wander very far if not supervised. This is dangerous. There also might be dogs, wildlife, or other cats that pose danger. Then you have roads, random plants they might eat, or rodents and birds they kill. If eaten, these can cause worms and other issues. In most cases, I don't think it's safe nor smart to just open up the door and let a pet out and go on about your business.

I disagree with you. I've owned cats for over 30 years and they've always been allowed to come and go as they please. The one I now own is 6 years old and spends most of her days and very often nights, outside. Her territory includes a main road, the nearby woods, a couple of fields and several houses where they have multiple dogs. She's a very savvy, independent cat and more capable of looking out for herself than many dogs. Two years ago I took her to the UK where she soon got used to living by an extremely busy road and the cats and dogs in the neighbours gardens.

Stray cats attack at night here. Also, my cat went missing for 2 days once. She was all the way in the next neighborhood. My cat might be stupid, but I'd never do it. All depends on the cat and the environment. Our other cat cannot climb anymore, so cannot escape well if she needs to. It's not for me.