This is an argument that shows up a lot. An action X, which is actually good, is deemed to be bad, because if X was coupled with something else, Y, then things would be very bad. Hence, since X gets us halfway towards this very bad state, X itself must be bad (assume that the goodness of X is far insignificant compared to the badness of X and Y together).
Is this argument sound? Is it a fallacy?
I have a hard time figuring it out. I think it kind of comes down to whether the goodness of X outweighs the increased probability of ending up in an "X and Y"-situation? So perhaps the flaw in the argument is that it assumes everybody is as risk averse as the one making the argument? And, in fact, a further flaw is that the argument does not actually argue what the exact or estimated increase in probability is, thus the argument is also incomplete?