I know what you said, but wanted to temper it.
Inter-service rivalry is indeed alive and well. You can toot your USMC horn all you want, but have the decency not to denigrate other branches of service in the process, ok? It's only fair. Likewise, slow promotions
never happen in other branches of service. That's why I punched out after 20 years instead of going 30. Reindeer games are reindeer games, regardless of service. Brown-nosing is very much equal-opportunity in that respect.
Now, I'm well aware that the Marines are usually the first in to harm's way, and expect to suffer the highest casualties when things get messy. They have a job to do, and that's why they're Marines. What the Marines cannot do, the SEALS and other SpecOps folks take care of in the hierarchy of force. That's well and good, since the USMC is administratively assigned under the Department of the Navy - amphibious warfare just wouldn't look right being administered by the Army.
I'm also under no misconceptions that combat and its effects on the human psyche are exclusive to the USMC, as much as some Gyrenes like to think.
By way of exposure, my wife was a Marine. So was her ex-husband. Her dad is a retired one-legged Marine GySgt who's on those films taken during the Evacuation of Saigon, and he's got no problems thwacking somebody with his prosthetic leg - the proverbial one-legged man in a butt-kicking contest, personified. There's more Devil Dog paraphernalia in this house than USAF, save for my office. My wife looks at my framed B-52H and WC-135W pictures and grunts, "Airplane!"