Listen up, John Oliver, you fish-eating Brit.

You can say whatever you want about Ryan Lochte, Donald Trump, Republicans, Democrats, Budweiser, the current state of journalism, America’s charter schools and the bizarre way so many people in our country pronounce “Target.” (Tar-ZHAY, anyone?)

But somebody forgot to tell you before you crossed the pond that there are some ironclad rules to survival in the U.S. of A., one of which was inexplicably removed from the final draft of the Declaration of Independence:

We hold this truth to be self-evident: You don’t mess with the Philly Cheesesteak.

So we have to ask: What on earth were you thinking last week on your HBO show, "Last Week With John Oliver?"

During a lengthy vivisection of America’s charter school system, Oliver noted that Pennsylvania’s auditor general said his state had “the worst charter school in the United States.”

And then you went off the rails:

“That is not good. It is not like having the worst ‘something’ is new for Pennsylvania. Remember, this is the state that has the worst football fans, the worst bell and the worst regional delicacy. Yes. If I wanted Cheez Whiz on my steak sandwich, I’d eat at Kiddie Cafeteria, the restaurant run by 6-year-olds.”

Needless to say, this breach of diplomatic protocol did not go unnoticed in the City of Brotherly Love. Philadelphia Mayor Jim Kenney, who doesn’t have a show on HBO, had to offer his rebuttal on Twitter:

Pennsylvania Sen. Anthony Hardy Willians even weighed in on the controversy, saying the host went "too far" in his attack-- and vowed to stop watching Oliver's program altogether.

"I really do enjoy your wit and informative style," Williams wrote in a letter , "but you went too far with your segment on Pennsylvania's charter schools."

He added, "By the way, you also forgot to mention in your 'charter schools are terrible' commentary that this is also the state where traditional public schools have some major challenges."

And of course there were other comments from diehard cheesesteak fans that echoed the lawmaker's sentiments:

So, if we may, John, we’d like to offer a few words of friendly advice if you ever choose to visit Philadelphia:

No. 1: Don’t visit the Liberty Bell. Somebody might recognize you.

No. 2: Don't attend any Eagles games. Somebody might recognize you, and they may have had several beers.

No. 3: Avoid places named “Pat’s” and “Gino’s.” Trust us on this.