It doesn't, which is exactly the point. Actions of private citizens don't have to be expressly mentioned in the Constitution for them to be permitted. If the Constitution doesn't expressly mention and ban political parties, then they're perfectly legal.
I wouldn't think that needed to be pointed out, but apparently, it did.
“It doesn’t, which is exactly the point. Actions of private citizens don’t have to be expressly mentioned in the Constitution for them to be permitted.”
And when other citizens do not approve of their actions, they have to right to petition for redress of grievances. Which Cruz and his supporter then conveniently call, “whining.”