President-elect Donald Trump got straight to tweeting on Tuesday morning, first by going after CNN for their support for Democratic nominee Hillary Clinton during the election, which he won. He then went after people who burn the American flag.

In one tweet, Trump suggested that people burning the flag — a form of speech with which he does not agree — should either be imprisoned or stripped of their citizenship.

Burning the American flag is protected by the First Amendment. This was decided in the 1990 Supreme Court case, United States v. Eichman. 

According to the ACLU, “Flag burning and desecration is offensive precisely because it is political. Experience shows that the way to fight political expression with which one disagrees is not to outlaw it, as Congress has repeatedly sought to do, but to express disapproval.”

Trump wrote of flag-burning, “Nobody should be allowed to burn the American flag – if they do, there must be consequences – perhaps loss of citizenship or year in jail!”

Nobody should be allowed to burn the American flag – if they do, there must be consequences – perhaps loss of citizenship or year in jail!

— Donald J. Trump (@realDonaldTrump) November 29, 2016

It remains unclear about what exactly he was referring to, but the people of Twitter had a lot to say about his controversial message.  

TRUMP: all brown people are illegal and you have to kiss the flag every morning@nytimes: Tongue or No Tongue? Our Guide to Flag Kissing

— JK Rowlet (@jephjacques) November 29, 2016

Don’t let Trump’s tweets distract you from the real issue: how Jeremy Renner was totally mis-cast in Arrival

— Abraham Riesman (@abrahamjoseph) November 29, 2016

Let’s burn this. #trumpflag pic.twitter.com/8JB2M6o2EZ

— Mike Pomatto (@Mike_Pomatto) November 29, 2016

One of the worst parts of trump’s presidency is going to be all of the quote tweets when he says something horrifically dumb everyday.

— chaps (@UncleChaps) November 29, 2016

First they came for the 1st Amendment. Then the 14th, 15th & 19th. When Trump is done 2nd will be all that’s left https://t.co/PJgPlF8I3C

— Ari Berman (@AriBerman) November 29, 2016

Nightmare scenario on display this am: Pence quietly working to dismantle Medicare while Trump attacks people & threatens civil liberties.

— Matthew Miller (@matthewamiller) November 29, 2016

How much do you want to bet that Trump doesn't know that the proper way to dispose of a torn damaged American flag is to burn it?

— Katie Sherrod (@KatieSherrod3) November 29, 2016

Trump does it again! The last time Congress proposed a Flag Protection Act it was written by….Senator Hillary Clinton!#4DChess pic.twitter.com/TFRlIpBLRU

— Jack Posobiec (@JackPosobiec) November 29, 2016

Trump loves the flag so much that he got five draft deferments to avoid seeing any burned in Vietnam

— Emma Roller (@emmaroller) November 29, 2016

If you don’t count flag-burners & the country’s most populous state, Trump won the popular vote. https://t.co/gHXTnTys7h

— David Frum (@davidfrum) November 29, 2016

Trump is going to turn flag burning into a noble act https://t.co/74tNai8Cyp

— Jon Andreassi (@JonCAndre) November 29, 2016

Hey #trump, today is flag burning day. Come on over and watch.

— WE'RE SCREWED (@jimmywhiz) November 29, 2016