In my travels I frequently meet folks who just cannot believe anyone would amputate a horse's tail. When they look at, for example, the Budweiser Clydesdales whose tails are all cut off, bone, tissue and all, they truly think the hair is just trimmed, or, the tail is folded in half.
Tails have bones in them. The average adult horse has 18 vertebra in their tails. Docking cuts off around 15 of those, leaving a tiny, useless stub. I was horrified one day when I heard an announcer talking about the Budweiser Clydesdales telling an audience that their tails were "bobbed"...and wasn't that cute!
I put together two images for you to look at where you can see Clydesdales in Britain on the left. Can you see how their entire tail is still there, it has just had the hair clipped off, leaving longer hair on the top to make the decorative bun. On the right are some Clydesdales who, unfortunately, all had their tails docked.
Hopefully, this clears it up for some folks the difference in appearance between a normal tail and a docked one.