It is precisely because we cannot know in advance the consequences of each and every action that we need rules to guide us. Rights and moral rules provide the boundaries of action, but they are not an end in themselves. They are means to achieving good consequences. That is, one could wholly agree with the approach recommended above in terms of how to establish general rules of conduct as hypothetical imperatives which assume the facts of reality and human happiness as a goal, and then without logical contradiction assert that the ideal version of such a system would be socialism. In fact, I think is how most of the more notable socialists did argue in favor of their position.
Human beings are purposeful, teleological, goal-directed beings.
Some well-intentioned defenses of socialism are quite thorough and compelling, and it would take far more than one paragraph to adequately handle the host of arguments. All other rules are corollaries, or derivatives, of these basic imperatives. The empirical evidence is overwhelmingly suggestive that more lives could be saved, more people steered away from drugs, more taxpayer money saved, if we just ended the war on drugs and legalized them. I recall how I was first steered toward the classical liberal tradition. This is basic epistemology, after all.