South Korea and Japan fight over a group of guano-covered rocky islets in the sea between them. They argue over their recollections of history in the first half of the 20th century, when Japan colonized the Korean Peninsula.

Now, they're arguing over pretzel sticks dipped in chocolate.

Today, Nov. 11, is Pepero Day. Well, it is if you’re in South Korea. If you’re in Japan, it’s Pocky Day.

Not letting any commercial opportunity slip by, food companies in both countries have turned 11/11 — a date marked by four long lines — into a celebration of their respective long and skinny snacks.

And, as with so many issues between them, there’s a dispute about who “owns” the day, something that has escalated as each company promotes its product in the other country — and farther afield in Asia.

In Japan, Pepero has gained popularity thanks to the “Korean wave” of films and music. In South Korea, Japanese products are still widely considered more high-end than homemade ones.

The fight says much about the similarities, as well as the antagonism, between the two countries.

Some background: There is no doubt that the treat originated in Japan.

Ezaki Glico, the Japanese confectionery company, brought out Pocky in 1966, promoting it as a “snack with a handle,” as the chocolate doesn’t extend all the way to the bottom. The name Pocky represents the snapping sound made while eating it — pokkin pokkin — to the Japanese ear, the company’s Web site says.

Lotte Confectionery, a South Korean food company, started making a strikingly similar product — while denying it had copied Pocky — called Pepero in 1983.

But the dispute arises over who commercialized 11/11 first. Lotte presents this as an organic event that began in the mid-1990s when middle-school girls in South Korea started exchanging Peperos, promising each other that they would become as skinny as the sticks. It took off. Now, sales from the Pepero Day season, which extends from September to November, account for as much as half of Lotte’s annual Pepero sales, according to Yonhap News.

This year, consumers are expected to spend up to 20 percent more for the day, as it falls one day before the College Scholastic Ability Test, Hankook Ilbo reports.

In Japan, Nov. 11 is officially known as Pocky and Pretz Day, including its plainer, non-candied pretzel cousin Pretz, since about 1999.

Glico has emphasized the originality of its Pocky snack, particularly through social media marketing. In 2012, it set a Guinness World Record for the most-tweeted brand name in a 24-hour period. There’s a Pocky-themed dance contest with J Soul Brothers, a music group, and a festival in Osaka, in collaboration with Tsutenkaku, the landmark tower.

As Nov. 11 dawned in Asia, both companies launched social media campaigns. People, both ordinary and famous, posted photos of themselves celebrating with the stick snacks.

Seems everyone can agree on one thing: Chocolate-covered pretzels are delicious. And that, if nothing else, is a marketing triumph.

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