Innovation should be purposeful, not whimsical. That’s the message from Naval History and Heritage Command historian Tyler Pitrof’s book Too Far on a Whim: The Limits of High-Steam Propulsion in the U.S. Navy, new in print out of the nautical climes of Tuscaloosa, Alabama. It hooked me because it promised to take me back to those thrilling days of yesteryear when I was a twentysomething engineer overseeing a high-pressure (600 PSI), high-temperature (850o F) steam propulsion plant of the type whose history Pitfrof chronicles. His book looked like an education on part of my own heritage.

And by no means does it disappoint on that front. But there’s far more to the appeal of Too Far on a Whim than nostalgia or mere scientific-technical interest. What Pitrof really provides is a case study on the promise—and the perils—of technical innovation. The danger part is the important part. Rather than grasp at the latest shiny bauble, he opines, institutional leaders must demand that realistic field testing vindicate its merits. In short, the scientific method must prevail. This is sage counsel that the contemporary U.S. armed services must heed.

But it’s a message that could get lost. Nowadays military magnates clamor constantly for the services to innovate. By that they chiefly mean harnessing novel technology to keep abreast of the likes of China’s People’s Liberation Army. The Pentagon has instituted a Defense Innovation Unit. The individual services have set up kindred innovation centers of their own. And there is no gainsaying the need to stay in tune with changing times and circumstances, especially with the rise of dynamic, domineering competitors like China. In fact, adaptability is a must. Thinkers from the Renaissance Florentine philosopher-statesman Niccolò Machiavelli to U.S. Air Force colonel John Boyd attest to it. Machiavelli and Boyd beseech rulers, diplomats, and warriors to constantly take stock of ambient surroundings and amend habits of mind, heart, and deed to keep up with change. Only thus can institutions of state prosper.

Willingness to change constitutes the essence of statecraft.

But it’s easy to get carried away in the quest for the next big thing. Not all change is for the better. Just because some widget, tactic, technique, or procedure breaks with the past does not make embracing it necessary or good. In fact, some innovations are downright harmful. They consume resources while supplying little return on the investment. Or as Pitrof observes, even an innovation that’s helpful in some ways may entail unintended, unwanted, and fateful consequences that outweigh its value. Such, he writes, was the case with high-pressure steam in the prewar and wartime U.S. Navy. The system fell short of the claims made for it while imposing unforeseen stresses on both fleet operations and the industrial complex entrusted with furnishing the fleet with hulls, munitions, and warmaking matériel of all sorts.

A disappointment all around.

And this apparently innocuous technical choice—a type of power plant—had strategic repercussions. The transition to high-pressure steam slowed construction of the two-ocean U.S. Navy, granting imperial Japan time to run wild in the Pacific. If not for the June 1942 miracle at Midway—a battle fought not with new-construction ships of war but with remnants of the fleet decimated at Pearl Harbor—the Pacific War may have traced a different and more disquieting trajectory. Small-seeming decisions can yield colossal effects.

The small-seeming decision to make “high-steam” propulsion universal in surface warships came at the behest of one man, Vice Admiral Harold G. Bowen Sr. Admiral Bowen headed the U.S. Navy’s Bureau of Engineering (BuEng) at a time of transition in the late 1930s. In effect he was the chief engineer of the Navy. He championed the new system tirelessly and on assorted grounds, mainly logistical. War Plan Orange represented the Navy’s blueprint for a counteroffensive across the Pacific to rescue the Philippine Islands from a Japanese assault. But carrying out the plan threatened to overstrain U.S. naval logistics. The Navy had neither fighting ships with sufficient range, nor a combat-logistics fleet adequate in numbers or capability, nor—in the post-World War I era of naval arms control—the naval stations to support the U.S. Pacific Fleet as it lumbered westward toward its reckoning with the Imperial Japanese Navy.

Reducing the fleet’s demand for supplies was crucial.

Fuel in particular. To wage war across the empty vastness of the Pacific, executing Plan Orange, fleet designers needed to lengthen the operating range of the navy’s surface combatants. Destroyers constituted the biggest design challenge. Tin cans were needed in bulk to protect aircraft-carrier and battleship formations from surface, air, and subsurface attack. Major combatants boasted capacious bunkers and could voyage long distances before refueling. Winsome destroyers did not, and so wringing additional steaming range out of their meager fuel capacity was a must for the prewar navy.

Bowen promised that high-pressure steam would deliver sensational increases in cruising radius. Intensifying pressures and temperatures within propulsion plants, he said, would let engineers extract more energy from superheated steam—steam so hot it’s completely moisture-free—using the same amount of fuel oil as lower-pressure plants. More energy, greater fuel economy; greater fuel economy, greater operational reach.

QED.

And this was a proposition eminently worth putting to the test. Trouble is, Bowen was no Wayne Meyer. Admiral Meyer was the father of the Aegis combat system found in frontline U.S. Navy guided-missile cruisers and destroyers from the early 1980s forward. He made his credo build a little, test a little, learn a lot. He preached an experimental ethos grounded in the scientific method. Meyer was humble about his creation. He understood that any newfangled piece of kit, no matter how promising, remains a hypothesis until it proves its worth through realistic field trials.

Aegis did that.

Bowen was impatient by contrast. He kept pushing to install high-pressure steam in new ship classes before performance data came in from fleet engineers operating classes already thus equipped. Moreover, he espoused even higher pressures, up to 1,200 PSI steam for new battleships. This before 600 PSI plants had proved their mettle at sea.

He got his way for quite some time despite the naval establishment’s mounting unease at the scope and velocity of change. Pitrof maintains that Bowen was able to argue from authority because he alone was well-versed in high-steam technology. No one among U.S. Navy line officers—a community that prized generalists over specialists in engineering or other niche disciplines—felt competent to overrule his zealotry. In late 1938 the Navy General Board, an advisory body made up of gray-haired eminences, convened hearings to review the pros and cons of high-pressure steam propulsion. The board threw up its hands in its final report: “The Navy Department has gone too far on a whim to walk back on a hunch.”

How’s that for hard-hitting analysis?

In other words, the General Board inverted the burden of proof. Because board members could not disprove Bowen’s brief for high-pressure steam, and because the U.S. Navy had lavished resources on it, they chose to submit to the BuEng overseer’s expertise and hope for the best. Board members, then, succumbed to two logical fallacies in their report. Rather than insist that high-steam propulsion undergo rigorous at-sea testing before the Navy adopted it wholesale, they let an argument from a single authority pass without challenge. And they reasoned that the resources the Navy had plowed into high-steam propulsion in the past mandated that the service keep investing in the system. Sunk costs dictated future policy.

Error compounded error.

Pitrof goes on to catalog the dislocations caused by the premature turn to high-pressure steam. It’s not that the system was a total failure. It drove hulls through the water, and it did improve the fleet’s operational range. But only by about two-thirds of the figure Bowen had forecast. The shortfall rippled into tactics, operations, and even strategy for the Pacific War. How was it that the BuEng chief, a brilliant officer by most accounts, overestimated the new plants’ performance? According to Pitrof he drew false analogies from other fields of endeavor. For example, high-pressure steam plants acquitted themselves well in generating electrical power for American cities. They also sufficed for merchant shipping, which as a general rule plodded along at steady, economical speeds.

But wartime is not like peacetime. Civilian power plants and merchantmen operate under steady-state conditions that limit how much fuel they consume. Ships at war have no such luxury. Naval task forces commonly have to advance at faster-than-economical speeds to assemble at the time and place of battle. That shortens vessels’ range. Captains tend to keep all of their machinery running, rather than idle some of it to save fuel, so that they have backup equipment at the ready should their ships suffer battle damage. Redundancy makes a ship thirsty for fuel. Warships also maneuver radically when they fall under attack. Sudden transients—much like flooring the gas pedal—burn fuel in alarming quantities.

In short, the exigencies of naval warfare curtail the distance ships can steam without refueling. Such realities were largely invisible in Bowen’s arguments for high-pressure steam.