The first two reasons we can't trust Iran are the fact that they keep saying "destroying Israel is not negotiable" and they continue to chant "Death to America." I would think that's enough for all Americans to say "No" to any deal with Iran.
They hate Israel, and they hate the United States and won't be happy until we no longer exist. I realize that there are probably thousands of Iranians who are peace-loving people and just want to continue their daily lives like we do, but the powers to be in Iran don't have the same feelings.
The last thing we should do is start dismantling our nuclear weapons for that very reason. We must remain on the defensive.