I asked specifically about missles designed to shoot down planes for a reason. If I need to explain it to you, you are demonstrating quite nicely why true libertarianism is insanity.
Letters of marque.
Militia.
Second amendment.
Ever hear of any of the above?
Now not everyone agrees with me, but if a person has the means to purchase the item, there are provisions for private ownership if arms and systems.
But if you are asking me if YOU should, no I don't. I don't think YOU should have access to anything more dangerous than a soda straw.
But I think you ought to have the freedom to play with your soda straw as much as you please without government interference.