The gauntlet has been thrown.
Credit: LauriPatterson/Getty Images

The Chicago Police waged the ultimate war on New York this week—and the NYPD responded accordingly.

Here’s what led to the social media battle for the ages:

First, this tweet happened.

Then, this tweet happened.

That’s pretty much it. But still—them’s fightin’ words, CPD!

I don’t care if National Pizza Day is this weekend: You don’t mess with a city’s signature foods, especially when that city is New York.

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If you’re not familiar with the differences between Chicago-style pizza and New York-style pizza, you should know that the debate pretty much comes down to the sheer size of the pie.

New York pizza is known for thin, crispy crust topped with a thin layer of tomato sauce, cheese and assorted toppings, according to, while Chicago’s slice features a thick crust with an inch-deep smothering of tomato sauce, cheese and toppings.

Of course, loyalists on both sides of the pizza aisle got involved in the argument:

We expect this battle will continue to rage until National Pizza Day (February 9), and probably long after. Because, you know, there’s not enough room for two types of pizza in this country.