WASHINGTON — The Pentagon is poised to order the military services to review more than 1,000 medals issued since the 9/11 terror attacks for possible upgrade to the Medal of Honor, the country's highest award issued for valor in combat, according to documents obtained by USA TODAY.

If approved by Defense Secretary Ash Carter, the sweeping review would represent one of the most significant steps in decades to honor troops who have displayed extraordinary courage in combat. The review stems from a study of military decorations and awards that was ordered in March 2014 by then Defense SecretaryChuck Hagel "to ensure that after 13 years of combat the awards system appropriately recognizes the service, sacrifices and action of our service members."

Should even a fraction of the medals under review be upgraded, it's possible that dozens more troops would receive the Medal of Honor for their bravery in Iraq and Afghanistan.

The Pentagon had no immediate comment on the documents.

Among the other recommendations forwarded for Carter's approval:

A new award for troops who have directed drones over battlefields in the Middle East and Afghanistan. The "R" device would be awarded to "recognize remote impacts on combat operations."

Establishing a standard definition for meritorious service that limits combat awards to those exposed to hostile action or at "significant risk" of exposure.

Setting goals and guidelines to ensure Medal of Honor and other awards are made in a timely way.

The proposal for potential upgrades to Medal of Honor has the potential to be the most controversial. Of the 37 recommendations, it was the only one not reached by consensus, records show. It would require the Army, Air Force, Marine Corps and Navy to re-examine each of the Service Cross and Silver Star nominations they have awarded since Sept. 11, 2001. The Army alone awarded 718 Silver Stars.

Related: Military Times Hall of Valor

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The Army and Air Force plan to review the Service Crosses and Silver Stars each branch has awarded. But the Navy and Marine Corps oppose such a review, according to a briefing paper, because top officials there "believe reviewing prior decisions undermines the integrity of commanders' decisions." The Marine Corps is a department of the Navy.

A memo from Navy Secretary Ray Mabus added that such a review "may have long-term detrimental impact on our service culture and our awards program."

Mabus' memo goes on to note that the Pentagon certified in 2010 that the services' Medal of Honor "processes and standards were sound."

A history of the Medal of Honor For more than 150 years, the Medal of Honor has been the U.S. military's highest award for acts of valor above and beyond the call of duty.

"Much of the prestige of our valor decorations stems from confidence in the process before awarding them," the memo says. "Reconsidering all previous valor award decisions without an evidentiary basis would reverse the longstanding policy that protects the integrity of the process by which we award our highest decorations."

Part of the rationale for the recommendation to review the Service Crosses and Silver Stars, according to another briefing paper, is that prior from 2001 to 2010, all the Medals of Honor were bestowed posthumously. After this Pentagon guidance was issued, "there is no requirement to meet the 'risk of life' portion of the (Medal of Honor) award criteria all recipients have been living."

In addition, the paper notes, "Combat experience of commanders differed early in the conflict and this lack of combat experience may have led to an initial reluctance to recommend members for the (Medal of Honor)."

The review included input from more than 1,000 combat-experienced troops at 13 posts, according to another paper.

The most recent recipient of the Medal of Honor was Army Capt. Florent Groberg. He was serving on a personal-protection detail on Aug. 8, 2012 when his patrol was ambushed by two suicide bombers. Groberg grabbed the first bomber and pushed him away, triggering an explosion that severely wounded him but saved several lives.