Just keep repeating this until the election:
Iran has completed a new phase in its Arak heavy-water reactor plant, a presidential official said on Saturday, referring to part of Iran's atomic programme which the West fears is aimed at producing bombs.
The official said President Mahmoud Ahmadinejad would give a speech later in the day "announcing that the heavy-water project has become operational".
A heavy water plant is a significant development. In nuclear power plants that use heavy water, unenriched uranium can be employed, as opposed to light water reactor plants which require enriched uranium. More significant however, is that spent uranium fuel from heavy water reactors can be processed to produce plutonium, the other element other than the U-235 isotope of uranium that can be used to build the core components of atomic weapons.
So, this is nothing to take lightly. However, Iran is not presently in a position to make plutonium. For that you need a heavy water reactor. Iran has a heavy water reactor in production, but it is not scheduled to be completed until 2009. In other words, there is no imminent threat of Iran constructing nuclear weapons using the reprocessed spent fuel from a heavy water reactor.
It will take time to run the plant long enough to produce enough spent fuel for reprocessing into plutonium. In the meantime, Iran's heavy water plant and its heavy water reactor would be easy targets for an aerial assault by missiles and or bombs.
Go read the whole thing, it's a good discussion of what does, and doesn't matter.