Our interest in pandas has always brought out the best and the worst in us.

In 1936, a wealthy Manhattan adventurer, Ruth Harkness, returned from China carrying the first live baby giant panda seen in the United States, setting off what many punning headline writers would forever call “panda-monium.” Thousands of Americans jostled to see this creature. Reporters, photographers and newsreel cameras chased Ms. Harkness. Time magazine called the panda “Animal of the Year.” Theodore Roosevelt III, the former president’s son, held the baby on his lap; the famed wildlife artist Charles Knight sketched portraits. Curious Americans couldn’t get enough.

Yet just a few years later, Ms. Harkness became heartsick over what she’d helped unleash. Squads of panda hunters began fanning out to “bag” more of the animals (despite the Chinese government’s efforts to stop Westerners from leaving the country with pandas). The treatment of these animals in captivity more broadly horrified her. So she did something amazing: From the city of Chengdu, she took a recently captured young panda, hiked into the mountains and set the animal free.

America’s obsession with pandas has swelled since that time. Washington mourned when the pandas at the Smithsonian’s National Zoo went back to China late last year. Its residents are elated to know a new pair of pandas will arrive at the zoo later this year. Another pair will arrive at the San Diego Zoo. As Americans gear up to greet pandas once again, we should remember that our infatuation with these animals requires a commitment to treating them with reverence and solicitude — because their presence improves us, and the planet, in ways that transcend the sheer joy of observing them.

Over time, the fortunes of these sensitive, charismatic creatures have risen and fallen like companies on the stock market, thanks to the collision of conservation forces, bureaucracies and international diplomacy. China has for decades offered these animals to our zoos as high-priced loans; in the 1980s the practice became best known as lucrative, short-term “rent a panda” programs. Safeguards were later put in place by the U.S. government and the Association of Zoos and Aquariums to ensure that profits were poured into conservation.

Pandas are more than objects to be shipped overseas. They are the rarest bear species on earth, and they live quiet lives in the mountains of China, vanishing into the vegetation when humans appear. As the great field biologist George Schaller wrote, these bears with a meat eater’s digestive system and the diet of a vegetarian are “as improbable as a carnivorous cow.” Unlike any other bear’s, their pupils are vertical, like a cat’s. And their method of mating in captivity seems anything but, well, productive. When they do conceive, their babies are born vulnerable and tiny, comparable in size to a stick of butter. (Case in point: One of the National Zoo’s most famous former resident pandas was nicknamed Butterstick.)

Our extreme attraction to pandas comes down in great part to their physical traits reminding us of baby versions of ourselves, but even cuter and more exaggerated: large heads, wobbly beach ball bodies, dark patches that make their eyes look bigger. They sit up to eat like a child does, and they hold their food with the help of a sixth digit that makes their paws look like mittens.