It's best when the photos and other posts we put up here on FR are verified to the greatest degree possible. I hope we are not slipping in that regard. I've now found a few other photos of that day... it's not that hard to do. Captions and links are above each photo. The third one is during the National Anthem (presuming that the caption at the source web page is correct).
U.S. President Barack Obama is saluted by Admiral Michael Mullen, left, Chairman of the Joint Chiefs of Staff, and Major General Richard Rowe, commander of the Military District of Washington, D.C., during Memorial Day Ceremonies at Arlington National Cemetery in Arlington, Virginia, on May 25, 2009.
http://www.upi.com/topic/Michael_Mullen/photos/pg-2/
President Barack Obama and Adm. Michael Mullen, chairman of the Joint Chiefs of Staff, bow their heads during a Memorial Day ceremony today at Arlington National Cemetery.
http://www.commercialappeal.com/news/2009/may/25/memorial-day-compromise-obama-sends-wreaths-confed/
Navy Adm. Mike Mullen, chairman of the Joint Chiefs of Staff and President Barack Obama render honors during the playing of the National Anthem during Memorial Day commemorations at Arlington National Cemetery, Arlington, Va., May 25, 2009
http://www.jcs.mil/newsarticle.aspx?ID=97
President Obama pays tribute to veterans at a wreath-laying at Arlington National Cemetery on Monday [5-25-09].
http://www.cnn.com/2009/POLITICS/05/25/obama.memorial.day/index.html