The lessons never learned from the Pearl Harbor attacks

Perhaps the most stunning aspect of the Pearl Harbor attack in 1941, the incident of infamy that finally thrust a burgeoning superpower fully into World War II, is that the U.S. knew something was going to happen and failed to anticipate it.

In the lead-up to the U.S. declaring war on Japan and eventually Germany, American intelligence had cracked Japan's diplomatic codes and knew that it was considering attacks in retribution for a U.S. oil embargo.

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"Why, with some of the finest intelligence available in our history, with the almost certain knowledge that war was at hand, with plans that contemplated the precise type of attack that was executed by Japan on the morning of Dec. 7 – Why was it possible for a Pearl Harbor to occur?" the Senate committee that investigated the attack pondered in its 1946 final report.

The committee struck on a key limitation of American national security that pervades to this day: the debate over whether enough processed intelligence could ever prevent a surprise attack from taking place, whether a sea-based assault by a sovereign nation, or 19 extremists hijacking four commercial planes. The legislators in the aftermath of World War II designed specific recommendations to resolve this problem, and yet history and current events show that it remains.

Among the subsequent investigators' conclusions was that the U.S. military and intelligence gathering agencies didn't have the necessary coordination to make informed conclusions and then act on them. These shortcomings in part were resolved by the resulting 1947 National Security Act, which established the Department of the Defense, the CIA, the White House's National Security Council, and the national security adviser, the counselor tasked with helping the president manage these elements.

But human error, too, played a significant factor in the Pearl Harbor attacks, despite the committee's overarching conclusion that the official blame lay with the Japanese alone. The U.S. commander at Pearl Harbor knew, for one example, that a Japanese submarine was sunk in the mouth of the harbor the morning of the attack, and yet anti-aircraft gun crews stationed there weren't poised to defend against a larger assault. Ships at the base were grouped together and planes were in their airfields to prevent sabotage, which the U.S. military at that time considered the most credible threat.

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"It's impossible to prevent surprises," says Ron Spector, a professor at The George Washington University and a specialist on 20th century warfare and U.S. relations with Asia. "The secret is how well you're equipped to survive a surprise, and then rebound from it."

He notes that in this case, the U.S. was able to restore much of the fighting strength of its Pacific fleet by 1942.

The history of war has counted few incidents of intelligence adequately preventing a surprise attack. Cracking the Japanese code in the 1930s allowed American commanders afterward some advantage over their Pacific foes, such as in the Battle of Midway.

The preponderance of subsequent conflicts, however, show continued failures by major powers to foresee battlefield surprises, like Chinese attacks in the Korean War, the beginning of the Tet Offensive in 1968, the Yom Kippur War in 1973, and the 9/11 attacks in 2001.

Pearl Harbor was supposed to serve as a lesson that American popular disapproval for going to war should not have allowed its government to fail in preparing for one. Yet that attack, particularly, has established a unique legacy in American history.

"It's a metaphor," Spector says, "but it's lost some of its metaphorical meaning over the years."

"Pearl Harbor" began as a rallying cry to inspire patriotism among Americans after World War II. It morphed into a quippy way to criticize the Japanese and German attempted takeover of the U.S. auto market in the 1980s.

In more recent years, it has served as a way for informed officials to offer their most dire warning about a threat for which the U.S. is not prepared. Then-Defense Secretary Leon Panetta used the phrase in 2012 to raise awareness about the potential for a cyber attack that could cripple America's power grid, transportation system, financial networks and even the government itself.

One of the attack's other important lessons is how it demonstrated the failure of deterrence.

Throughout the 1930s, Japan invaded China and what is now Indonesia. It began a military campaign in Vietnam and was preparing for one in the Philippines – then a U.S. colony – when Washington slapped an oil embargo on Japan, hoping that would be enough to freeze its military ambitions.

"We thought we could deter the Japanese attack by economic means, by economic embargo, and really trying to isolate Japan diplomatically," says Kurt Piehler, a professor at Florida State University and director of its Institute on World War II and the Human Experience. "The question is, was war worth protecting China? Were war interests so paramount?"

"They didn't really ask the question, 'Are we ready to go to war with Japan?'"

The situation at Pearl Harbor the morning of Dec. 7 served as the definitive answer.

Piehler sees continued examples of America's underestimating its adversaries. On Sept. 11, 2001, the U.S. didn't have clearly established procedures for military fighter jets to intercept hijacked commercial planes whose pilots had turned off the transponders, for example, because nobody had seriously prepared for an attack of that nature on the homeland. Hawkish critics of President Barack Obama's foreign policy today say his unwillingness to get more involved militarily in places like Syria or Ukraine – a "Plan B" to diplomacy – allowed Russia to believe it can pursue its foreign policy interests unmolested in those countries, and perhaps even elsewhere in Europe.

"Pearl Harbor has many lessons, but one of those lessons is the need to critically imagine possibilities, and to think hard. Adversaries don't often act the way we think they do, and you have to make sure you have a Plan B," Piehler says. "Americans are largely unfocused about defense policy, and even foreign affairs. One of the things that's striking to me: This may be an era where the old World War II consensus is breaking down."

That post-war consensus of stability in Europe has remained since 1945, with the exception of a few regional wars. But now, a resurgent Russia with NATO responses, along with the complexities of modern warfare, make the next conflict difficult to predict.

"The ultimate responsibility for the attack and its results rests upon Japan," the Senate committee concluded in 1946. Finding someone to blame may have helped explain the beginning of that war, but that understanding likely won't help prevent the next one.

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