I've found myself in an awkward position defending sanctions I don't really agree with anyway. I'm not sure these differences of opinion are reconcilable. Some people think the appropriate response to death threats is to ignore them, and others like me think the appropriate response is a cruise missile.
You realize that "Death to America" is not remotely a death threat? At worst it wants to see the fall of America and most Iranians say they just want the end of America's imperialist policies.
And you're against sanctions because they don't kill enough people.