Earlier this month, the Russian government announced it was looking to buy five combat dolphins: two females and three males, physically unblemished, and in possession of “perfect teeth.” Naturally, Russia did not reveal what it planned to do with the dolphins. That allowed the Internet to have a field day speculating for what nefarious tasks these dolphins might be used—including recovering sunken torpedoes, killing enemy divers, or planting bombs.

But Russia wasn’t being serious, right? Well, actually, it probably was. For Russia, dolphin deployment is nothing new: During the Cold War, the country used these slippery soldiers to do things like detect submarines, flag mines, and protect ships and harbors, according to retired colonel Viktor Baranets. In fact, countries have been enlisting these smart, adaptable creatures to perform underwater military tasks for more than 50 years.

But let’s be clear: Assembling a dolphin army wasn’t the Russians’ idea. It was ours.

The story of America’s war dolphins starts innocently enough. In 1960, military researchers wanted to design better missiles. And dolphins—graceful, lithe, aerodynamic in the water—seemed like the perfect animal to imitate. However, upon examining a female Pacific white-sided dolphin named Notty, researchers quickly realized that dolphins weren’t just well-designed. “They were also trainable, and adaptable, and amenable to training,” says Ed Budzyna, a Navy spokesman. “That led to … other things.”

“Other things” became the U.S. Navy Marine Mammal Training Program in San Diego, California, which today houses 85 bottlenose dolphins. (This is down from peak-marine mammal reserves, which occurred in 1995 when the U.S. possessed more than 150 trained dolphins and belugas and nearly 50 sea lions.) Before settling on dolphins, the Navy also tried out other marine mammals. For example, they found that killer whales could recover objects at depths of 1,654 feet, while white whales, or belugas, could dive up to 2,100 feet. But when it came to precision, no other cetacean could outperform the dolphin.

The choice to use dolphins to perform military tasks is a logical one, says Terrie Williams, a large mammal physiologist at the University of California at Santa Cruz who has studied dolphins since 1990. “If you wanted a water watchdog, that’s what I would choose,” she says. She should know: Williams, who has published studies on dolphin diving physiology, worked as a researcher in the Marine Mammal Program during the 1990s. Why not sharks? “For the obvious reasons,” she says—training sharks is both harder and potentially more dangerous.

Navy dolphins are trained mainly in two tasks, neither of which involve combat. First, they are taught to find underwater mines—often ones that are tricky to locate, half-buried, and hundreds of meters deep—so that the Navy can map their presence and avoid them in combat. Second, they learn to flag the presence of enemy swimmers, again to alert the Navy rather than attack. To do this, dolphins work with handlers, who equip them with conical buoys around their snouts. When a dolphin finds a swimmer, it releases the buoy, which floats up and flashes so forces can find the swimmer.

In these arenas, dolphins have two qualities that make them unbeatable: diving and sonar. Like most cetaceans—the order of marine mammals that includes whales, dolphins, and porpoises—dolphins can dive deep, for up to 10 minutes at a time. Once they have identified an underwater object, they can reach it quickly and efficiently. But their sonar, says Williams, is “off the charts.” She describes dolphin sonar as akin to being able to take X-ray after X-ray of your surroundings and then compiling them into a 3-dimensional picture.

“We barely have calibers to measure the way these animals are able to differentiate between things in the water,” she says. “No technology has been able to match it yet.”

In other words, they’re basically the world’s best fetchers.

Budzyna agrees. As technology gets better, it’s possible that the Marine Mammal Program will be rendered obsolete, he says. But right now, when it comes to locating underwater objects—and particularly enemy swimmers, who are more dynamic and unpredictable than stationary mines—you just can’t beat dolphins. “They’re just extremely well-adapted to their environment,” he says.

So even though the Marine Mammal Program has been around since 1960, its dolphins have never actually seen combat, says Budzyna. The closest they’ve gotten was during the Vietnam War, when they were deployed to protect ships and submarines at the American base in Cam Rahn Bay. This happened again during the Iran-Iraq war, when they were used to watch vessels and a floating helicopter platform in the Persian Gulf, according to the New York Times. Additionally, during the 1996 Republican National Convention in San Diego, dolphins and their handlers were on standby in the waters next to the Convention Center, according to Budzyna—but fortunately, their services weren’t needed.

In the 1980s, the Navy flirted with the idea of using dolphin guards to patrol the Trident nuclear submarine base in Washington. According to the Times, the dolphins would “detect possible saboteurs.” That plan was foiled by animal rights activists, who sued in 1989, blaming the death of one dolphin during training on the Navy’s allegedly cruel practice of making warm-water animals work in icy conditions in Puget Sound. The Navy settled the suit, agreeing to both suspend the project and stop taking dolphins from the wild.

On purely emotional grounds, there is something perverse about the idea of using a dolphin as an instrument of war. We’re taught to think of dolphins as the hippies of the animal kingdom: social, emotional, gregarious, giddy. They break into chirping laughter. They protect their loved ones. They even practice free love. When we picture a dolphin, we see a playful creature bobbing above the water’s surface, mouth broken open in what we see as a wide, toothy grin. (That’s to say nothing of their renowned intelligence and prodigious memories.)

The U.S. has always claimed that it has never trained dolphins to kill. It has made this assertion despite the fact that former Navy dolphin trainers have said otherwise, including Richard L. Trout, a civilian mammal trainer for the Navy from 1985 to 1989, who told the New York Times in 1990 that Navy dolphins “were learning to kill enemy divers.” But using dolphins for combat purposes “just wouldn’t make sense,” says Budzyna, who believes much of this speculation came out of the 1973 movie The Day of the Dolphin. “They’re not trained to make decisions,” he says. “So it would be ridiculous to expect them to make choices underwater as to whether it’s a friend or a foe and what they should do about it.”

But Russia, which started investing in marine mammal programs in 1965 after witnessing the U.S.’s success, has made no such promises. So could Russia be training its war dolphins to kill enemy divers? I asked Williams how dolphins might be used for more odious porpoises—I mean, purposes—than flagging mines. After dismissing the idea of equipping dolphins with knives or bullets on their heads as “pretty far-fetched,” Williams did admit that, conceivably, you might train dolphins to ram an enemy swimmer as they do sharks in the wild, butting them again and again with their hard snouts.

“Are they capable of doing it? Yeah,” she says. “They can bust up a shark pretty good.”

But in the wild, ramming a shark isn’t a common occurrence, it’s a desperate measure of self-defense. Since their heads house their delicate sonar equipment, dolphins are more likely to protect it rather than repeatedly bash it against something, Williams says. And beyond ramming, a dolphin doesn’t have aggressive jaw capabilities; their teeth are meant merely for grabbing fish, not ripping and tearing. “There are behaviors you can build off of,” Williams says. “But the training would be hard for the animal. Not because it’s a pacifist, but simply because it’s not built to do those kind of tasks.”

Don’t just take it from her. As other former military experts told the Times, dolphins are simply too “benign and unreliable” to perform these kinds of tasks. Perhaps the most adorable testament, from Trout:

”When they were supposed to ram us with the guns,” he said, ”they either swam away or put their snouts on our shoulders, very affectionately. They were the worst at taking orders.”

Williams adds that, given the years of training the Navy puts into them, these dolphins are invaluable. If you had to put dollar price on them, they’d be worth hundreds of thousands, if not millions, of dollars—as compared to the $25,000 Russia was reportedly starting its bidding at. That’s yet another reason not to send them into active combat: It would be a waste to put such a valuable piece of “military hardware” on a mission where it would be exposed to lethal dangers. “These weren’t suicide mission animals, by any stretch of the imagination,” says Williams. “Never.”

(The fact that almost all U.S. military dolphins survive their experience introduces the strange question of how such a creature retires. After all, bottlenose dolphins can live 40-45 years in the wild. Budzyna says they generally remain under the military’s purview, for use in research projects.)

At any rate, it’s impossible to know exactly what plans the Russians have for their new recruits. But if they’re looking to train dolphins to kill, they probably won’t get terribly far. Here’s to hoping that these mammals’ docile nature will save them from the worst that warfare has to offer.