Getting out of the sanctions business

What nations has the U.S. sanctioned?

I don't have an exhaustive list, but some that come to mind are:

Cuba 

Venezuela 

Iran

Russia.

I'm sure there are others.

Have those sanctions yielded good results?

More significantly, 

should the U.S. be telling other nations how to run their affairs?

If, for example, Iran is a theocracy, what business is that of the U.S.?

Why can't they be a theocracy?

How does that impact the U.S.?

Of course, not at all.

For other U.S. sanctions, see

https://en.wikipedia.org/wiki/United_States_sanctions