When people think of battles won and lost throughout military history, they envision overwhelming firepower, diverse strategies and tactics, armies underestimating their opponents, or even bad luck. However, very few imagine operations in which soldiers suffered significant casualties despite the absence of enemy combatants. Yet this is what happened during Operation Cottage, when the Allies invaded Kiska Island in 1943.
Operation Cottage was meant to eliminate the last Japanese foothold in North America. The goal was to remove nearly 5,000 Japanese soldiers believed to remain on Kiska Island, just as forces had clung to their position on nearby Attu Island.
Both American and Canadian strategists expected a difficult battle in a harsh environment, but instead, they encountered an island abandoned weeks before. Yet Allied troops suffered hundreds of casualties.
To understand how this was possible, we must first consider the events that led to Operation Cottage and the year-long campaign that occupied the Aleutian Islands.
Understanding the Aleutian Campaign
West of Alaska, a chain of volcanic islands called the Aleutian Islands stretches across the Pacific Ocean. These islands are home to freezing temperatures, frequent storms, dense fog, and intense winds that make them inhospitable for the majority of the year.
However, this did not deter Japanese forces, who, in 1942, moved against the Aleutian Islands as part of their major offensive against Midway Atoll. In the course of this operation, the Japanese forces occupied both Attu and Kiska, islands within the Aleutian chain.
Japan was rapidly expanding across the Pacific, but these islands were the only American territory they had claimed during the war. Historians are not all in agreement about why the Japanese leadership so ardently pursued claiming Kiska and Attu.
Some say that it may have been a diversion to draw American attention away from Midway. Others suggest that Japanese forces wanted to claim potential bases that the US could later use to establish and launch future operations. No one is certain of the motivation, but what historians know for sure is that the United States would not accept Japanese troops on American soil.
The occupation of the Aleutian Islands was a symbolic challenge more than a tactical one. In addition, some military planners warned that Japanese control of the islands might threaten shipping routes in the North Pacific, but this was viewed as a lesser risk.
However, just as the Allies had failed to utilize the islands for their own efforts due to the environmental conditions, the Japanese forces discovered that holding the islands proved difficult. Transportation and communication were cumbersome or even impossible for some stretches, and supplying isolated garrisons required consistent and significant naval resources.
The United States responded by bolstering military activity around Alaska. Throughout 1942 and ’43, American planes bombed both Attu and Kiska. It also employed ships despite the treacherous waters, but soon enough, military engagements in the area became more about surviving the weather than gaining new ground. Allied planners agreed in 1943 that this constant churn of mobilization, which did nothing but leave troops fighting the weather, needed to end, and they agreed to target Attu Island once and for all.
The Battle of Attu and Evacuation of Kiska
The American operation into Attu began in May of 1943. Forces encountered strong resistance from the Japanese, and even after the conclusion of the war, the Battle of Attu was considered one of the most difficult Pacific campaigns.
In part, this came from the tenacity of the Japanese defenders, but the island itself posed issues. Without roads, soldiers needed to advance on foot across steep mountains, bogs, valleys, and snow-covered ridges. Throughout all of this, the weather remained frigid, and soldiers could rarely see because of the dense fog.
Meanwhile, the Japanese had been there for long enough that they had established strong positions. Every step forward came at a cost for the Americans, as they struggled to coordinate across difficult ground without breaking away from supply lines. Injured soldiers were poorly cared for, as medical evacuation was even more difficult than forward progress, and equipment malfunction was common in the wet and freezing conditions.
The Japanese commanding officer, Colonel Yasuyo Yamasaki, resisted until American troops had pushed too far. Then, on May 29, 1943, Yamasaki initiated one of the largest banzai charges of the Pacific War. His troops charged in at once, penetrating into the American line to initiate close-quarters fighting. Although the Japanese troops were defeated and their garrison destroyed, American casualties exceeded 3,500 killed or wounded.
American commanders learned a valuable lesson from Attu. Even in the most favorable circumstances, the Aleutian Islands were a costly place to do battle. Thus, when attention shifted toward reclaiming Attu’s neighboring island, Kiska, planning already took into account a situation poised to be a repeat of Attu. In other words, military leaders expected a heavily defended island occupied by thousands of Japanese troops willing to give anything to defend their positions. This was the assumption that undid Kiska later.
Operation Cottage: Casualties Without the Enemy
Taking note of what had occurred at Attu, the Allies assembled 34,000 troops to overtake the Japanese at Kiska with overwhelming force.
These troops comprised both American and Canadian units on foot, as well as battleships, cruisers, destroyers, and auxiliary vessels. Alaskan air forces ran numerous bombings in an attempt to weaken Kiska’s defenses before the invasion began in earnest.
Commanders briefed their units extensively on what to expect based on the events at Attu: fierce combat, and especially surprise attacks from concealed positions that used Kiska’s geography against the opposition. Soldiers were primed to expect the worst.
Meanwhile, naval bombardment and air strikes intensified as the invasion date closed in, with thousands of tons of bombs striking suspected Japanese installations. But recon reports only confused strategists more. Some suggested that the island appeared uncannily quiet.
Others argued against this point, stating that the Japanese troops were simply succeeding at concealing their activities. This only prompted an even more intense anticipation of resistance. As the Allied forces failed to provoke any response or evidence of movement from Kiska, commanders feared that the Japanese may have been deliberately attempting to lure them in with a false sense of security.
After so long without any confirmation of Japanese presence, a few senior officers began to seriously posit that the Japanese garrison was gone. But for the majority, the invasion remained the right choice. If the Japanese were there, then approaching with force and preparation at a time of their own choosing provided the best chance of success. And if they weren’t? Their cautious approach would merely result in wasted time.
However, things did not play out in this manner. Operation Cottage commenced under conditions similar to what the Allied forces expected: dense fog and harsh weather. Cohorts landed on multiple sides of the island, and initial reports were encouraging. No landings encountered opposition.
This silence only increased suspicion and led many officers to advise that troops remain hyper-alert for ambushes from concealed positions as they moved inland.
Soldiers were on edge, exacerbated by the fog that reduced visibility in some areas to no more than a few dozen yards. Navigational errors compounded in this environment, and soon enough, troops that were meant to stay in close contact had drifted apart.
Soldiers moving across the island discovered abandoned equipment and deserted defense positions. Again, this was taken as evidence that the Japanese had moved inward, to prepare for more intense action. Within this environment of stress and mental strain, the atmosphere grew tense among the Allied forces.
As the operation continued, things began to unravel. Separate American and Canadian troops, having drifted through the fog, often lost the ability to reestablish their positions relative to each other, as terrain interfered with radio transmissions.
Thus, when soldiers encountered unfamiliar figures in the fog, they engaged as if they were the enemy. Unfortunately, several firefights erupted between Allied forces, sometimes for extended periods, before realizing that they were attacking each other.
Dozens had died before commanders recognized that the Japanese forces had long since abandoned the island. Though they determined that retreat was the best course of action, the casualty number only continued to grow.
The former Japanese garrison had constructed extensive defenses, including mines and other hazards, in addition to the risks posed by the terrain itself. Troops exploring these abandoned positions occasionally encountered explosives that further increased the death count. Slowly, troops confirmed that the island was deserted. But still, the deadliest incident was yet to come.
While troops searched the island, naval forces stood by. On August 18, 1943, the destroyer USS Abner Read struck a Japanese naval mine near Kiska harbor, blowing the vessel’s stern to pieces and wounding the sailors aboard.
Though the crew barely managed to save the ship, the 71-man death toll constituted the largest individual strike of Operation Cottage, and it occurred without any Japanese soldiers present.
Why Did Operation Cottage Happen the Way It Did?
The primary question of Operation Cottage is why it happened in the first place. How did more than 30,000 people fail to notice that they were fighting no one? Numerous factors come into play. First and potentially foremost was the influence of Attu.
Commanders were ardently educating soldiers on what to expect so as to avoid a repeat of the thousands of lives lost at Attu. While this could have served troops well in combat, it was what primed them to overreact once they found the island bare.
The expectation of ambush attacks and fierce resistance led to what psychologists refer to as “expectation bias”: the tendency to interpret information in a way that is consistent with what one believes. The soldiers anticipated Japanese defenders arising from the fog, ready to fight. When they encountered Allies, their expectation informed their actions.
Another factor was the challenge of intelligence collection. Both the geography and weather of Kiska made information gathering nearly impossible. Aircraft could rarely observe the island through the fog, coupled with cloud cover, and although evidence suggested that activity on Kiska had fallen, numerous additional possibilities could have explained it.
The Japanese were able to evacuate Kiska Harbor due to the cover of fog, and the local weather made reconnaissance into the harbor a challenge for the Allies who wanted to investigate. In fact, the Aleutians have earned a reputation for some of the worst weather encountered during the war. For commanders who wanted to attempt naval or air intelligence gathering, intense wind and storms made the decision for them in many cases.
Operation Cottage did not go as the Allied leadership planned, but in a way, it did succeed. The Japanese occupation in the Aleutian Islands ended, at least in part because of Attu, but possibly because of the threat of Kiska as well.
Historians note that these battles are some of the most frequently forgotten among the war’s many conflicts, but they are a window into the decision-making process of wartime commanders. Decisions are rarely made with perfect (or even substantial) knowledge; rather, leaders must interpret incomplete evidence and evaluate possibilities according to what is most likely to have the greatest effect with minimal loss of life.
In the case of Kiska, commanders chose incorrectly, but they did so based on the information they had at the time and the knowledge that, should a Japanese presence still be brewing in Kiska, it could pose a significant threat to the Allies in the Alaska region later.
While Operation Cottage is far from unique in terms of battles that took unexpected turns, it stands among the few well-documented instances of friendly fire that resulted in significant same-side losses. While modern technology has improved in its capabilities to prevent a similar event in the future, military leadership will always need to make split-second decisions on less than comprehensive information; the environment that created Operation Cottage will likely never be fully preventable.
