If the US is trying to destabilise the country, and manage to cause a revolution, then I am certainly in favour of that course of action.

Terrorist bombings in New York didn't "cause a revolution" - they swung people behind the government, and helped it to get away with doing some very stupid things. Why should anyone expect it to be any different when the bombings are in Tehran?

Whether the USA is behind the bombings or not, most ordinary Iranians are likely to believe that it is. In any case the effect will be to make it harder for patriotic Iranians to criticise or oppose their government.

Previous actions by the USA in the region played a major part in the victory of more extremist politicians such as Ahmadinejad in the last elections in Iran. (Yes, they do have genuine elections in Iran, and governments can lose them. And that is why Ahmadinejad is in power.)