Understanding the National Defense Service Medal

 In History and Traditions

The National Defense Service Medal is one of the most common awards authorized to Service Members in the United States. The award, sometimes abbreviated to NDSM, was established in 1953 by President Eisenhower. Originally intended to recognize service in the Armed Forces during the Korean War, the award now indicates service during specified periods.


The award was designed by Thomas Hudson Jones in 1953. Jones designed more than 40 other U.S. awards, including the World War II Victory Medal.  His best known design is the Tomb of the Unknown Soldier.


The ribbon is scarlet with a yellow center stripe flaked by narrow red, white, blue stripes.  The red ribbon is symbolic of Mars, the Roman God of War, and also represents fortitude and courage.  The center strips of white, blue, scarlet and yellow are taken from the American Defense Service Medal, which is a pre-World War II award on which precedence the NDSM is based.  The yellow stripe represents the opportunity to serve, and it is flanked by the national colors.

The medallion of the award bears and eagle with inverted wings, standing on a sword and palm. The words “National Defense” are above the eagle, following the curve of the medal.  The eagle is the national symbol. The sword represents armed strength while the palm represents victory.  The inverted wings of the eagle are meant to signify readiness.


Two of the most frequently made mistakes in wearing this award is mixing it up with the similarly named American Defense Service Medal, and including subsequent awards for the same period.  You may have heard, “I was deployed twice to Afghanistan. I rate that star on the NDSM.” or Or, “But guys, I’m SURE I rate the American Defense Service Medal.”

Award Periods and Rules, In Brief:

Here’s a cheat sheet for the NDSM:

  1. The National Defense Service Medal (NDSM) is awarded during strict “windows”. Those windows are for the Korean War, the Vietnam War, Operation Desert Shield / Desert Storm, and the Global War on Terror.
  2. The NDSM was first established for service from July 27th, 1950 to July 27th, 1954 to indicate active service in the Korean War. The requirement during this period was “honorable active service as a member of the Armed Forces”
  3. During the Vietnam War, the NDSM “Window” was opened on January 1st, 1961 and closed August 14th, 1974. Like the Korea period, the Vietnam requirement was “honorable active service as a member of the Armed Forces”
  4. The next window was for the 1st Gulf War, or Operation Desert Shield / Desert Storm. The opening date was set at August 2, 1990 to November 30, 1995. For this period, members of the National Guard and Reserves were included. Essentially, the “honorable active service” was changed to “Service in good standing in the Active, Reserve and National Guard Components”
  5. The final window began on September 11, 2001 and has not yet ended. Like the Desert Shield / Storm period, “Service in good standing in the Active, Reserve and National Guard Components” is required.

That’s it; nothing more, nothing less. If you meet the requirements for any period, you rate the award. Even if you were in Recruit Training or OCS when the window closed, you rate the award. However, you can only receive the award 1 time per period. You don’t get a star each time you deploy to a combat-zone, or if you re-enlist during a window as some some folks mistakenly believe.

It’s a good measure of a person’s period of service

The NDSM is a good tool for evaluating when a person was in the service. For example, if a person has 1 star on their NDSM, they were in during

  • Korean AND Vietnam Wars, OR
  • Vietnam AND Gulf Wars, OR
  • Gulf War and GWOT,

It’s possible to have broken time between windows, i.e. a Vietnam Vet gets out for a long time and rejoins the National Guard after 9/11. However, the same periods apply to everyone.

By comparing campaign awards with the presence of the National Defense Service Medal, you can get a good indication of when someone was active in the Military.

If a 34 year old person is wearing 2 stars on a NDSM, someone needs to square him away. They were not born during the Vietnam period and they were, at best, 15 years old when the Gulf War period ended. There is a lot of rumor that get spread around by people who don’t know what they are talking about. If anyone says you can wear 2 awards of the NDSM in any 1 period, THEY ARE WRONG. If, however, meet the criteria for 2 periods, but only one is listed on your discharge documents, you should apply to have your records corrected.

Another source of confusion: the ADSM vs the NDSM



The other common misunderstanding is the difference between the National Defense Service Medal and the American Defense Service Medal. LOTS of people mistakenly wear the latter, when they are actually authorized the former. Though they have very similar names, the American Defense Service Medal was awarded to people who were volunteers in the Armed Forces prior to the draft in World War II. The period for eligibility for the ADSM ended in 1939, and it has never been awarded since. So, if we see a person with Liberation of Kuwait medals, an ADSM, but no NDSM, it’s a safe bet that they got their wires crossed.

Here is an example from the Korean War era where a soldier rated both an ADSM and an NDSM:


Here’s what we can discern from this partial record:

1. We know the person joined Prior to 1939. (ADSM)
2. We know he was on active duty during Korea, but never went to Korea. (NDSM, No Korea Medals)
3. Likely spent time in West Berlin AFTER the Korean War (Occupation Medal,Dates)
4.This person probably spent AT LEAST 28 years in the service. (AFLSAx5 (1947 to 1967) + 1939 to 1947 = 28
5. He would have 1 Star on the NDSM for Vietnam (1961 – ) if he was on Active duty. As he doesn’t, we can assume that he was in the reserves or National Guard during the Vietnam NDSM window.

I hope this is helpful and informative. The National Defense Service Medal has been awarded to millions of service members, but is often misunderstood. Additionally, many people who are fraudulently wearing awards mess up the NDSM, but you can’t see the target they painted on themselves unless you understand the regs.

For Reference:
Army Institute of Heraldry

Air Force Awards FactSheets

National Defense Service Medal @ Foxfall

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