It would appear, on the surface, to be one of the dumbest ideas on earth — falsifying or editing military intelligence reports to conform to the wishes of political leaders. Not surprisingly, the outcome is rarely positive.

One of the starkest examples occurred in the early days of June, 1967. Much of the world was taken aback when Israel, outnumbered in every strategic category, scored a completely one-sided victory against four much larger nations — Egypt, Syria, Jordan, and Iraq. The element of surprise helped and the Israeli military was better trained, but a key factor can be gleaned from Michael Oren’s 2002 book, “Six Days of War.”

Mr. Oren interviewed military participants on both sides and disclosed a diametrically opposed use of intelligence. Egyptian officers feared giving bad news to their superiors and especially to their leader, Gamal Abdel Nasser. So after Israel’s initial attack that destroyed the Egyptian Air Force on the ground, the Egyptians falsely reported to their superiors and their allies that the opposite had occurred, that they had inflicted huge Israeli losses. This left Syria open to the same fate and brought Jordan into the war.

The Israelis, on the other hand, were stone cold realists. When their pilots returned from the first sorties and reported their astounding success, Israeli leaders were at first skeptical. They wanted corroboration and said nothing to the press. At the same time, many high-ranking Egyptian commanders continued the lie or went into hiding.

The public reaction was equally lopsided. Egyptians celebrated in the streets during the first two days, while Israel went silent. Israeli leaders understood that the public would be deeply worried, but the news blackout gave Israel’s ground troops the chance to score a second decisive victory. The devastating truth did not really come to light until the third and fourth days.

That story offers little comfort here in the U.S. after reports surfaced recently that Centcom, which oversees our effort against ISIS, has been accused of cleansing intelligence reports to conform with the positive spin coming from the White House. The accusation of falsifying intelligence first came from two Defense Intelligence Agency analysts, who sent their complaints to the Inspector General at the Pentagon. It has since been backed up by more than 50 analysts.

There are few things more damaging to a country’s military than the accusation of cooking intelligence. It undermines morale and sows mistrust throughout the ranks.

There are many moving parts in war that are out of a commander’s control. But there are some aspects that a commander should be able to count on and honest intelligence should be near the top. When reports are misleading, the consequences can be catastrophic.

Intelligence failures have certainly led to battlefield disasters throughout American military history. Pearl Harbor, the Battle of the Bulge, the Chosin Reservoir, and the Bay of Pigs are among the most famous. But in each of these cases, the intelligence, while faulty or uninspired, was not doctored. Common sense and history should tell anyone that lies have a short shelf life in conflicts.

There is one little known, but important story from World War II that offers the opposite lesson. Less than a year after Pearl Harbor, in September 1942, Colonel Curtis LeMay was sent to England with 35 inexperienced B-17 bomber crews. The crews were so green that LeMay was unsure his pilots would actually make it across the Atlantic. He also understood that they would soon be going up against the vastly superior Luftwaffe.

LeMay and all Allied commanders faced a significant challenge — they had to create an entirely new science of warfare at the same time they were actually fighting. That their battlefield was 25,000 feet above the earth in machines that had really never been used before in combat made it all the more complicated. Understanding that he had to learn as much as he could as quickly as possible, LeMay developed a reputation for demanding honest data. If there was even a hint of false data, people were fired on the spot.

“I don’t have time to distinguish between the unfortunate and the incompetent.” He once said in explaining his brutal command style.

LeMay also began a procedure called the “closed door briefing.” After every mission an airman of any rank could say whatever he felt, even to the point of calling his commander stupid. Most importantly, LeMay made sure there were never any repercussions for this honesty. At first the airmen were hesitant, but when they saw he meant what he said and even promoted people who offered better ideas, the airmen opened up and everyone learned from the experience.

This was a radical concept, but LeMay understood that the only way his crews could improve and eventually defeat the Germans was by not surrounding himself with sycophants. Within one year, LeMay became the youngest general in modern U.S. history and his innovative tactics were quickly adopted by the entire Army Air Force. By D-Day, the Luftwaffe had been defeated and the Allies controlled the skies over Europe.

In many ways, LeMay viewed falsified data and the enemy as one in the same. He was determined to destroy both.

Today, ISIS, radical Islam and a belligerent nuclear Iran is a huge potential threat. Pretending they are not and rigging information to prove this is both unintelligent and highly dangerous.

Mr. Kozak is the author of “LeMay: The Life and Wars of General Curtis LeMay,” which was brought out in 2009 by Regnery.