You are right. A most important thing on dealing with Iran is to do it right: Hit selected targets to take out their leadership, military and nuclear facilities. Keep civilian casualties to a minimum to save the many, many pro-American Iranians. Then when the smoke settles, help them. It must be done in a WIN-WIN way for the Administration. Do not allow the Power hungry, America-comes-last leftist crowd to be able to take any credit. Make it a victory showing our moral authority over the left's immorality. A victory of Good over Evil. And RUB it in.
IMHO, Iran is now the key to the post-Saddam situation. If we can destabilize that regime and it falls, the picture completely changes. That would leave Syria the only remaining state supporter of the various terrorist groups in the region and I do not believe they could sustain that alone, cut off from Iranian money and support.