奥巴马总统在美国空军学院2016年毕业典礼上的演讲
Hello, Air Force! Thank you so much. Thank you. It is wonderful to be back at the United States Air Force Academy! Thank you, Secretary James, for your service to our Air Force and to our nation. Governor Hickenlooper, Academy leaders, faculty and staff – especially your outstanding Superintendent, Lieutenant General Michelle Johnson. And most of all, congratulations to the ...