president barack obama threw off the gloves and took a direct punch at one of his possible successors , likely republican presidential candidate scott walker , in an interview airing this morning .
responding claims that he 'd ` absolutely ' cancel or ` disown ' a deal with iran on ` day one ' if elected to higher office , obama told npr morning edition host steve inskeep that such an approach ` would be foolish .
' ` and , you know , perhaps mr. walker , after he 's taken some time to bone up on foreign policy .