The Trump Administration has just announced a 25 percent tariff on a large range of European Union products, including many cheeses. In a way, that’s good news because Trump had threatened a 100 percent tax. If you’d like to know which cheeses are affected, well, so would the importers. It’s complicated. A few well-known cheeses are indisputably on the hit list; others are questionable. But get ready for some sticker shock at the cheese counter.

The tariffs are in retaliation for illegal subsidies that the E.U. provided to Airbus, the aerospace company. So American cheese lovers and everyone in the cheese supply chain—makers, importers, distributors, mom-and-pop retailers—will be penalized for this cat fight between Boeing and Airbus. Makes perfect sense.

Weeks ago, the Administration was threatening to tax almost every EU cheese. The Final Product List is slimmer, thank goodness, but aggravatingly opaque. (“Cheddar cheese not subject to gen. note 15 of the HTS or to add. US note 18 to Ch. 4” means….what?) Importers and their Europe-based brokers are struggling to understand which cheeses are on the taxable list and which aren’t.

U.S. officials “were looking to pick the items that would have the biggest impact with the European producers, to upset them,” says Stephanie Ciano, vice president of international purchasing for World’s Best Cheese, a major importer in Somerville, Mass.

That theory could explain why Parmigiano-Reggiano, Stilton, Manchego and Greek feta are tariff victims. These cheeses are huge in the U.S. But, curiously, Camembert and Brie are exempt. In fact, France’s cheese producers escaped almost unscathed. Blue cheeses from Italy, Spain and the U.K. will be taxed, but most French blues get a pass. Most EU sheep cheeses will be taxed, but not the French ones. What’s up with that?

“This document has been poked at and paper clipped and edited to suit whoever can lobby effectively,” says Aaron Kirtz of Forever Cheese, a major New York-based importer. It certainly looks that way. Dutch Gouda escaped the tax. British Cheddar did not. It’s cheese gerrymandering, with lines drawn between the taxed and the untaxed for no legitimate reason.

For Customs purposes, imported cheeses are assigned to style categories, each with its own code. But whoever created the categories didn’t understand cheese. I’m particularly flummoxed by Section 11: 0406.90.57, a category subject to the new tariff. That’s for “pecorino cheese, from sheep’s milk, in original loaves, not suitable for grating.” Let’s overlook the redundancy. (Pecorino cheese is, by definition, from sheep’s milk.) But who decides that a cheese is not suitable for grating? I grate young ricotta salata (a sheep cheese) over pasta all the time. But I’m betting ricotta salata will be slapped with the duty while pecorino romano evades it. This is crazy making.

The tariffs are scheduled to take effect in mid-October, just in time to crimp your holiday entertaining. If you’re paying $18 a pound for Parmigiano Reggiano now, expect to pay $22 a pound or more as soon as importers sell through what they have stockpiled.

Trade talks continue and the Administration could presumably rescind the tariffs when it decides Europe has been punished enough.

“I’d like to think it won’t last more than a few months,” says Ciano, “but the Roquefort duty lasted 10 years. It’s definitely going to affect stores, and the fourth quarter is make-or-break time, particularly for independent shops. If they see a slowdown, their business might not be sustainable past this year.”