shorting requires margin account and uses margin. You will be charged money (margin interest) for shorts, so it does imply leverage as in NOT CASH, similar to margin lending (long). The "funny" thing about shorting is that you can easily lose MORE than you invested in comparison with long (non-leveraged) position as you can only lose whatever you invested and nothing more.
Similar, but not equivalent. You could argue that buying the instrument outright is a "leveraged trade" with leverage 1:1. Same goes for a non-leveraged naked short sale (with a leverage 1:1). Theoretically, you could lose infinite amount amount of money on a non-leveraged naked short, you are right. In practice, margin calls will probably kick in long before that.
just for the sake of it...
1. shorting is not allowed in cash accounts (like IRAs). Surely, it means that it is different from long in that respect. Long nonmargined positions do not result in any interest payments, but short positions always do. I fail to see how you can see those as basically identical.
2. Margin call warnings mean nothing when you get a gap up. Not only your position would be closed involuntarily (if it is below zero), but you would also experience a cash call on any liquid assets you might have (bank account, etc.)
