"Under the guidance of an expert, aides say Obama privately repeated his salute over and over again until he got it down. In a testament to how sensitive the White House is about the commander in chief practicing this basic military gesture, aides would not say who taught Obama how to salute. But every time he uses it, Obama is trying to convey an insider's respect for the armed forces without saying a word."
"That attention to detail, that focus on the outward manifestation of what we expect, is compelling," said retired Gen. Paul Eaton, who advised Obama during the presidential campaign. "Whoever worked with him on that did a pretty good job."
Here's the picture that accompanies the story:
I'm not sure if it's why the identity of his trainer is a State secret, but there's no evidence of that training here.