I lived in Delaware when Biden first entered the political arena and the Dupont Family anointed him as their Senator in 1973. He didn’t support the military then. When I joined the USAF in 1979, Biden didn’t have our backs except to stick a knife there. After I got out, his support of the troops was still as non existent as always. What changed?
If you're inferring that he now supports the military because he's the speaker that is not the case. The president typically gives the graduation address at one of the service academies every year, rotating through them. This year it's Air Force's turn, and they can't do a thing about it.