Last year, I did alot of research on Force Recon units and by the end of the day, I (bear with me, please) felt sorry for the Marines.
They have "Force Recon" which we all know is their version of SF, etc. These guys are airborne, scuba, etc.
Then there are battalion recon Marines, also better trained, but not at the Force level.
Well, in the early 80's, when SOCOM was being formulated, the Marines wanted no part of it.
Now, with SOCOM's huge budget and unlimited training abilities, they are the premier forces to be used when the shit hits the fan.
So, I read alot about Force Recon leaders whining that they continuously get passed up on missions because the National Command Authority always asks for SEALs, etc. It's popular to be a part of SOCOM, since those forces all train together with the air assets (160th SOAR, etc).
I even read of a senior Marine officer deferring a mission to a SEAL team, totally destroying the morale of the Force Recon unit involved. Don't remember the sources, but one Marine Captain said he was quitting over all of this.