You are correct, if there is a target in range when you attack, you will hit the target. There is no miss chance.
However, WHO you hit (with the basic attack at least) is randomly selected from the targets in range. Chrono was asking if there is a way to influence this random selection, to which the answer so far has been "don't know."
I strongly expect there to be a card in one of the 10 expansions Japan has that restricts the basic attack target selection, but that's Japan. I have yet to see a card in the basic set we're starting off with that affects the basic attack (other than cards that modify RNG).

