Current Wisdom
As far as I know, it's not Democratic policy to not worry about Iranian nuclear capability. It certainly is not Obama's. What is true wisdom is that we can't do much about it, and throwing tantrums on the world stage will not only accomplish nothing, it will make us look like fools.
Our best options are diplomatic, and perhaps covert. In either case, they will work better in the background.
Of course, it may be politically advantageous in the arena of domestic politics to bluster and make threats that can't be backed up with deeds.