So, Bush spends eight years puffing out his chest and threatening death, mayhem and an ass-whuppin' if Iran doesn't do exactly what he tells them to do. Accomplishment: Iran hid its nuclear facilities, informed the administration that they could go fuck themselves, and went on about their uranium enrichment.
Obama spends eight months in office, has a nice chat with Iran after letting them know that he's got both carrots and sticks on offer, their choice. Accomplishment: Iran's letting the inspectors in, shipping its uranium off to other countries where it can be enriched precisely the way we want it, and agreed to reduce its stockpile by 75%.
I rest my case.