Ahmadinejad has already reached these conclusions about Obama. If Barack wins, shortly after he takes office Iran will claim to have nuclear weapons capability. Obama will agree to meet with him and will grant them much of what they demand in exchange for agreeing to not sell or even test the weapons or attack any other countries. It will never be conclusively verified that they have nuclear weapons and no live nuclear tests will be demonstrated. Iran will be considered a nuclear power and will be able to dominate the Middle East while we will be required to pull all troops out of the region. Barack will comply as he had intended to do that all along and he will claim we have achieved an agreement with Iran that Bush failed to even attempt.
Within months of our complete withdrawal, Iraq will be toppled and Israel threatened sending oil prices skyrocketing. The economy that appeared to be on the road to recovery will crash even harder because of energy rationing and newly implemented carbon controls.
Al Qaeda begins to poke and prod at the US and our allies causing further chaos and instability. Afghanistan and Pakistan heat up into a full scale war with large numbers of troops being moved into the region.
Four years of Obama with a compliant Congress and a supportive media who dare not criticize him could be a long, long time.