Sanctions on Iran- will it work?

The US have decided to impose sanctions on Iran by not allowing US companies to have any ties with the Revolutionary guard. It was a step to deter any economy improvement in Iran and they would have no choice but got to stop processing any uranium enriched materials.

The argument from the US counterpart is that they accused Iran of hiding nuclear building materials and will use uranium to build weapons of mass destruction (had we have enough of this?). This time, the US government hopes that by cutting Iran's supply of cash will deter or cut down any form of support for terrorism.

I have no idea about it. What I can see from previous sanctions against North Korea worked because North Korea is so much isolated and they need external help and will not be able to help themselves at that point. Well, I don't think the situation have change since the sanction has drop against North Korea.

As for Iran, they are more hard headed. They will not give up easily. They do know that sanctions worked against North Korea but will it work for Iran? It did not work for them during the fifteen years of civil war. What would it takes to make it work if US is imposing economic sanctions against Iran?

What the US government want is simple - lay down their nuclear programme and help the world to fight terrorist. Will they listen to US? Will the sanctions work?