In the same vein, we should ban guns so criminals don't use them.
Criminals will do what they wish, regardless of law. As will socialists.
I cannot support restricting freedom because of what the base-minded might do with freedom. If a citizen abuses another, we as Americans must have an answer, sufficient to prevent a recurrence of the offence. If a citizen offends the rights of another citizen, we must have a punishment suitable for the greatest of offenses. That is what our Founders envisioned.
But an object, by itself, cannot reach that level of offense. A firearm (gun) is incapable of such an act. We punish the offender, not the object.