When former President Lyndon B. Johnson’s daughters smashed champagne bottles against a metal star atop the bow of the ship named for him last month, the crowd roared, patriotic streamers shot skyward, and there were smiles all around.

No one was churlish enough to mar the christening ceremony in Bath, Maine, by noting that in naming the futuristic-looking stealth destroyer for the 36th president, the Navy was honoring a part-time officer who spent decades wearing a decoration for valor that he knew full well he didn’t rate.

For most of his political life, Johnson proudly displayed a Silver Star pin on his lapel that identified him as a war hero. It can be seen in the famous photograph of his swearing-in on Air Force One after the assassination of President John F. Kennedy in 1963, in his official White House portrait, and in almost every formal picture in the LBJ Presidential Library in Austin, Texas.

But as a CNN investigation concluded definitively in 2001, the award was a sham, based on a myth that turned out to be a lie. I know, because I was the reporter who conducted that monthslong investigation along with producer Jim Barnett.

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“It is surely one of the most undeserved Silver Stars in history,” famed Johnson biographer Robert Caro told me at the time.

In 1942, Johnson was an ambitious young congressman from Texas who had been appointed a lieutenant commander in the Navy Reserve and had volunteered for active duty in the days after the Japanese attack on Pearl Harbor. As a sitting member of Congress, he successfully lobbied President Franklin D. Roosevelt to send him on an inspection tour of the southwest Pacific. It was in Australia that Johnson met Gen. Douglas MacArthur, who allowed Johnson to go on a single bombing mission as an observer.

On June 9, 1942, 11 American B-26s took off from Port Moresby, New Guinea, to attack a Japanese base in Lae, 180 miles to the north. The plane Johnson was on developed engine problems and returned to base without encountering the enemy, according to surviving members of the mission who were interviewed before they died.

Five separate accounts, along with military records, show that Johnson’s plane landed in Port Moresby shortly after 10 a.m., about the same time as the rest of the bombers were beginning their attack on the other side of the island. Johnson’s plane was the only B-26 that wasn’t listed as having sustained any damage from bullets in the Army’s after-action report.

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But in Johnson’s account, he watched as the crew fought valiantly to save the crippled plane while fending off a withering attack from Japanese Zeros. The myth was burnished in a laudatory 1964 book, The Mission, which described Johnson as “cool as ice” and “laughing” while bullets were “singing through the plane.”

Except it didn’t happen, insists retired Army Staff Sgt. Bob Marshall, who was a gunner on Johnson’s flight and the last surviving member of the crew.

“That was something I would never forget if I had to do that,” Marshall told me in 2001. “We never got attacked. I had no reason to swing my guns, my turret. Them was built up stories.”

In the LBJ Presidential Library, you can find a letter on congressional letterhead that Johnson addressed to the adjutant general of the War Department declining the Silver Star.

“I should not and could not accept a citation for the little part I played,” it reads. “The coolness for which the General commends me was only the reflection of the utter confidence in the men with whom I was flying.” Johnson could have sent the letter and returned the Silver Star.

Instead, he chose not to send it and to wear the lapel pin at every official occasion for the rest of his life, from time to time bragging about his fictional wartime exploits.

The U.S. Navy is rightly proud of its long legacy of seafaring presidents. Kennedy was awarded the Navy and Marine Corps Medal for his leadership after his motor torpedo boat, PT-109, was sliced in two by a Japanese destroyer in World War II. President Jimmy Carter, a 1946 graduate of the U.S. Naval Academy, was a submariner who was tapped by Adm. Hyman Rickover to work on the nuclear submarine program. President George H.W. Bush, at the time the Navy’s youngest pilot, flew 58 combat missions during World War II as a torpedo bomber. He was shot down in 1944 and later awarded the Distinguished Flying Cross for bravery in action. Presidents Richard Nixon and Gerald Ford were also naval officers.

All of those presidents have ships named after them, except Nixon.

In announcing in 2012 that the next Zumwalt-class destroyer would be named for Johnson, former Navy Secretary Ray Mabus cited his record of “bravely stepping forward to fight for his country” and his service “in the Pacific theater during World War II.”

One has to have some sympathy for the unknown junior officer who had to write up Johnson’s Silver Star citation for the nation’s third-highest military honor, which is awarded for “gallantry in action while engaged against an enemy.”

Johnson’s citation carefully avoids saying his specific plane came under fire from the enemy, noting it was forced to turn back before the attack and thus presented “a favorable target” to the enemy.

“He evidenced marked coolness in spite of the hazard involved,” the citation reads. “His gallant action allowed him to obtain and return with valuable information.”

The only other award for valor given out after that mission was a Distinguished Service Cross awarded posthumously to another member of Johnson’s inspection team who was on a B-26 that made it to the target, did encounter Zeros, and was shot down.

Lt. Col. Francis Stevens took Johnson’s seat on that plane after Johnson got off for a bathroom break. Johnson then boarded a different B-26, which history now records never encountered any hostile fire.

Jamie McIntyre is the Washington Examiner’s senior writer on defense and national security. His morning newsletter “Jamie McIntyre’s Daily on Defense,” is free and available by email subscription at dailyondefense.com.