It's not an ethical dilemma for me. It's the same as going long - buying something and placing a bet that it will soon increase in value. How is shorting worse than going long? It just feels unnatural to me.
Another way to look at it, if you are shorting Bitcoin against USD, then your are going long on USD against Bitcoin and vice versa so it is essentially the same ethical barrier to break either way.
@money-dreamer the difference between going long and short selling (in any type of investing) is that in a long position the seller receives the current present value of an investment and no longer has a vested interest in the transaction. Shorting an investment is similar to selling a lemon of a car, where the seller not only maintains a vested interest in the transaction, but naturally believes that the buyer is overpaying for the investment to the point where, by definition, the seller is wagering that the buyer has purchased an investment of diminishing value.
Putting a face to every transaction, going long is a vote of confidence in something/someone’s future via influx of capital. Shorting is a bet against someone’s success.
If you are shorting the USD against Bitcoin then you are betting that Bitcoin will do better than the USD. This can be done with Bitcoin or USD as collateral. There could be USD or Bitcoin as collateral, but it would be best to have the collateral as the same thing you are going long with. But, it would get liquidated faster if it is the same.