How should I feel if I missed out on a mission to a younger soldier with less experience than me?

Been there done that. When our Squadron was finally tasked with deploying persons to the Gulf for Shield/Storm I was the first volunteer, and the first person told no. The secondary argument was it was more a security oriented mission with no need for law enforcement types. I tried to argue that I had pulled way more security than some of the E2s and E3s at their first duty station that they might be taking while I was stationed in Turkey. Most of the time I spent in Turkey was training through NATO exercise after NATO exercise after NATO exercise, all of it focused on security oriented operations. It sucks but that's the military.

I never got to go, I was on the list for Gulf One, I was just never used, I'm total perm disabled now, I got the letter for being on the list to go, which helped certainly...a guy in our Pentecostal church my wife likes got to go, for which I obv envy him considerably, of course. Anyway, I thought to tell you a true story that might perhaps help, honest...my Dad was Navy just after WW2 into Korea, noncombat, a Grumman TBM av !mechanic at a Reserve unit in TN, that deployed once in awhile to the USS Block Island in the Caribbean...one time on leave, he was in a small candy store and restaurant, with my grandfather, in his Navy blues...a woman walked through, who's son was apparently in serious combat in Korea, and asked my Dad why he was sitting there, when her son had to be over there...my Dad said to her, the Navy knew exactly where he was, and if hey wanted him, they'd call, besides, he was legitimate leave...now, over the years, I've given that story a great deal of reflection, as you can imagine, as my next younger brother, who was USMMA Kings Point, I commissionedhim, I was USAF at that time when he graduated, his father in law was an Army cook mobilized during the Chosen reservoirs the whole thing, the real deal, he was lost fairly recently, our Dad about a decade and a half ago, I tried for my brother to find friends his father in law had enlisted with, I had some slight luck...anyway, I compare the two in my mind, our Dad and his father in law, my Uncle was a radio operator for Gen Eisenhower, my wife's Dad got a Bronze in Army in France going into Germany in WW2 her stepdad was Navy Pacific combat WW2 /Korea, so honestly, I can't judge, I just thought the story about our Dad might convey at least some level of moral aspect, neither good nor bad, just reality...I can perceive your thoughts, as I'd said, I'd wanted to go, I asked explicitly to go, I tried, I did, for real, I seriously asked, honest, it just wasn't !want to be...I just figured those stories might help, I'd be most eager for your thoughts, if you'd care to chat further...the thing with our Dad was obv some 60+ years ago, however, I do recall him telling myself and my next younger brother the story, as I'd said, many thanks....

No. I think you are just fine.