'Let's go Brandon,' explained

On Friday night, a Southwest Airlines pilot allegedly said "Let's go Brandon" over the plane intercom, causing a stir on board and prompting an investigation by the airline.

As CNN wrote:

"The Associated Press, which had a reporter on board the flight, first reported that a pilot of a Friday flight from Houston to Albuquerque ended his typical greeting to passengers with the phrase "Let's go Brandon," which has become right-wing code for 'F**k Joe Biden.' The AP report said passengers responded with audible gasps."

If you follow Donald Trump Jr. or any of the other lesser luminaries in the orbit of former President Donald Trump, you have seen their social media feeds full of these mock "Let's Go Brandon" cheers of late. Florida Rep. Bill Posey ended a speech on the House floor late last month with the phrase. South Carolina Rep. Jeff Duncan wore a mask on the House floor emblazoned with it as well. Texas Sen. Ted Cruz has said it's "one of the funniest things I've ever seen." There's now a "Let's Go Brandon" song and a "Let's Go Brandon" dance.

So, how the heck did we get here?