It was his political connection that got him on that shuttle flight.
The person who should have been on that flight was Chuck Yeager, a WWII ace, test pilot, who pioneered upper atmospheric flight, broke the sound barrier, built the base line for the Mercury 7.
He wasn’t flashy enough for them to make him an astronaut, but at the time they picked Glenn, he was still qualified and flying jet aircraft, and older than Glenn.
Don’t tell me his politics didn’t have anything to do with picking him.
Yeager openly looked down his nose at the NACA fliers that became our first astronauts. Decades later, he said that people had advocated for him to take a flight on the shuttle, but he saw no value in it.