Planes are no place for political tirades. At least not when you are flying with Delta Air Lines.

The airline found itself on the defense after it was criticized for how it handled a belligerent passenger on a recent flight. A passenger recorded a man who went on a tirade proclaiming “we got some Hillary b—-es on here? Come on, baby. Trump!” (amid a mix of expletives) as he stood in the aisle of a Delta dal flight earlier this month. The airline was criticized because the passenger, though disruptive and bellicose, was allowed to remain on the Nov. 22 flight from Atlanta to Allentown, Pennsylvania.

The video has been viewed more than two million times on Facebook alone.

On Saturday, over Thanksgiving weekend, Delta issued a statement apologizing to the passengers on the flight. But on Monday, Delta CEO Ed Bastian shared an internal memo that he sent to Delta’s staff, proclaiming that the airline would never allow that passenger to fly on another Delta plane again.

“After questioning the customer, our team members made the best decision they could given the information they had and allowed him to remain on the flight. However, if our colleagues had witnessed firsthand what was shown in the video, there is no question they would have removed him from the aircraft,” wrote Bastian in a memo with the subject line “Disruptive Passenger on DL248.”

He called the passenger’s behavior “loud, rude and disrespectful to his fellow customers.” Bastian also said that Delta had to admit it made a mistake in this case so it can learn how to more effectively handle these types of situations in the further.

Bastian said that the company would refund customers the cost of their ticket for that Atlanta to Allentown flight. He also apologized to the customers.

Part of why Delta was criticized is because some travelers have been booted from airlines for far less offensive behavior—often due to racial profiling. One American Airlines flight was delayed because an Ivy League professor’s math equations looked suspicious. In another case earlier this year, a man was booted from a Southwest flight because he had been speaking Arabic.

The statement from the Delta CEO concedes that airlines have to balance remaining committed to providing safe travel for their customers, while also treating those individuals with dignity and respect. That can be a tough balancing act to achieve.

“The heightened tension in our society means that now more than ever we must require civility on our planes and in our facilities,” Bastian said. “We must stay true to Delta’s core values and treat one another with dignity and respect. We also must remain committed more than ever to the safety of our customers and our crew members. We will not tolerate anything less.