Obama countered with a trace of sarcasm that he didn't understand some things - like how US could face the challenge in Afghanistan after spending years and hundreds of billions of dollars in Iraq.

奥巴马略带嘲讽地回击说，他确实不太了解一些事情，例如：多年来美国已经在伊拉克耗费了数千亿美元后，今后，美国要如何面对阿富汗问题的挑战。