I've had arguments with socialists so many times now that I can pin down and articulate a very simple, to-the-point argument for precisely why it is a bad thing. Before I do, it is worth saying that this is not an attempt to attack people for being socialists, I used to be one myself.
1. Socialism is a very complicated and intricate web of a doctrine, it is labyrinthine, which is why it is so easy to think the due diligence has been done and that it holds up. Don't be intimidated by any of it, because there is one simple thing that socialism rests on as an economic model:
Socialism requires the public ownership of the means of production. This basically means no private industry.
Look up any definition of socialism and this principle is always there, it is the very core of it, the entire point of socialism is to be a counter to capitalism.
2. The public is a hell of a lot of people. How can it own, operate, produce and distribute? Think of a room with 20 people in it and they have a single task to do, let's say preparing a presentation on.....the anatomy of crocodile penises. I dunno. Whatever. Now, to be able to decide how to approach the task, there needs to be a hierarchy, a way of organising and planning what is to be done and who is to do it. That's just one simple group of people doing one simple task. Now think of all of society and everything it needs to function, how do "the people" own and run it? Truth is, you need administrators, planners, who can make decisions.
3. In a society you also need rules, laws. Without rules nothing can actually be done at all. Once you have rules, how are they to be enforced? How can people be protected from rule breakers and those who wish to do them harm? How can the nation in general be safeguarded from invasion from outside? You'll need power, a monopoly on force, to do it.
4. We have administrators, we have a need for power/force. That means you need powerful administrators with people on their side in law enforcement. That means police and military. We now have a state.
5. Since nobody owns anything privately, the state now owns everything, because it has the monopoly on power. A state with such absolute power is a totalitarian state.
6. Since the state runs and owns everything, nobody can oppose them or have property the state cannot control. Which means whomever controls the state power controls the country. Those whom desire power the most are the most ruthless, which is why all governments, the world over, attract the most ruthless people. The system doesn't just fail to protect the country from a dictatorship, it necessitates one, so the country is ruled by the worst people, who own and control everything.
7. We are fucked. Goodbye liberty, goodbye ability to work hard to rise above your beginnings, you get what you're given and you do as you're told.
8. Nobody wants to live like this, which is why people in the affluent west never move to socialist states. Instead, the socialist, to maintain his illusion, must refer to capitalist democracies with large welfare states (such as Sweden, Norway or Canada) as socialist countries. In reality, they are mixed economies that are predominantly dependent on capitalist free enterprise. Since socialism must entail the public ownership of the means of production, none of the western capitalist democracies can be called socialist. Simply because no western democracy has surrendered the concept of private property.
9. It is over. Socialism is dead. It has been for decades and it is simply foolish and misguided to continue defending it. It produces the kinds of societies nobody likes living in or chooses to move to from the west. To push for something one doesn't want, on the pretence it will be "done right this time", when I have just shown it can never be "done right", is pure insanity.
10. We have always much to improve in western societies, there is always injustice to fight, progress to be made. But the solution can never be socialist. Ever.
