it's important that the protesters continue to broadcast to the world that they want a revolution, but they're largely wasting their time, on their own accord. there is no path to peaceful change in iran.
the question as to whether it's in us interests to intervene or not is an open question and i acknowledge i will not like the outcome, but this regime isn't going to be dismantled from the inside. overthrowing this regime will require the intervention of outside actors, and the use of violence.
the american tactic of generating unrest and provoking instability to topple governments without the use of military force requires some concept of democratic functioning in government as a prerequisite in order to be successful, even if the protests can get to critical mass. in the 21st century, critical mass will merely result in massacres and slaughter. populations cannot defend themselves with rifles against drones and tanks.
this tactic did not work in venezuela because the class divisions in the society were too deep for bourgeois support to get to critical mass, and there was simply no way to provoke enough unrest to topple the government, without first addressing the material conditions of workers, which workers understood would dramatically worsen in a return to banana republic economics and bourgeois democracy.
this tactic will not work in iran because the government would be just as happy to slaughter the apostates and do away with them than listen to them, anyways.