Being in the U.S. Navy for 7 years ,I learned a lot of military traditions and military rules  that must be followed. If these rules and regulations were not followed I was subject to punishment under the Uniform Code of Military Justice. So when  President Obama came down the steps of the helicopter and at the bottom of the steps a U.S. Marine saluted him the President gave him a half ass salute with a cup of coffee in his hand. The behavior of the President caused quite a stir. The Marine was saluting the office of the President . The return salute from the President was a tradition even if it was have ass. Upon some research the President is a civilian and not a member of the  military even through he is the Commander and Chief, only the members of the military are required to salute. So in all actuality the President really does not have to salute back. I was upset when I first saw the the half ass salute, but upon further research I must take it with a grain of salt.

Here is some information on saluting I found on the web. The first article was a real shock to me , due to the fact it was ingrained that a salute was always return . So check out this article.

http://www.texasgopvote.com/military-salute/it-proper-president-render-military-hand-salute-002816

Military personnel in uniform are required to salute when they meet and recognize persons entitled (by grade) to a salute except when it is inappropriate or impractical (in public conveyances such as planes and buses, in public places such as inside theaters, or when driving a vehicle).

Persons Entitled to a Salute

• The President of the United States (Commander-in-Chief)
• Commissioned Officers and Warrant Officers
• Any Medal of Honor Recipient
• Officers of Friendly Foreign Countries

A salute is also rendered

• When the United States National Anthem, "To the Color," "Hail to the Chief," or foreign national anthems are played.
• To uncased National Color outdoors.
• On ceremonial occasions (such as Change of Command, and Military Parades).
• At reveille and retreat ceremonies, during the raising or lowering of the flag.
• During the sounding of honors.
• When the Pledge of Allegiance to the U.S. flag is being recited outdoors.
• When turning over control of formations.
• When rendering reports.

Salutes are not required when

• Indoors, except when reporting to an officer or when on duty as a guard.
• Addressing a prisoner.
• Saluting is obviously inappropriate. In these cases, only greetings are exchanged. (Example: A person carrying articles with both hands, or being otherwise so occupied as to make saluting impracticable, is not required to salute a senior person or return the salute to a subordinate.)
• Either the senior or the subordinate is wearing civilian clothes (a salute in this case is not inappropriate, but is not required.)
• Officers of equal rank pass each other (a salute in this case is not inappropriate, but it is not required.)

Prisoners whose sentences include punitive discharges have lost the right to salute. All other prisoners, regardless of custody or grade, render the prescribed salute except when under armed guard.

Any military person recognizing a need to salute or a need to return one may do so anywhere at any time.