Failure to understand "Shadow Strike"

Good morning all. I have a lvl 31 Nightblade and have “Shadow Strike” at lvl 1. I put SS on my hotbar but when I click on it it does nothing. Why is that? Is it because it’s only at lvl 1? It says it’s active so passive is out. Does it have to be higher than lvl 1? Color me confused or just dumb. Thanks all.

Shadow Strike is an attack that requires a target to be used on, it is not a passive or toggleable skill. Try it on the training dummies in town or some random enemies.