When SOCOM was established in 1987, all the services were asked to subordinate their special operations forces to SOCOM. The marines were the only ones to refuse, partly on the grounds that they believed all their troops were elite, and partly because the only elite force (by marine standards) they had was Force Recon. But the marines could not give up Force Recon, as it was the strategic recon teams the marines used for their own operations. But, under pressure from SOCOM after September 11, 2001, the marines agreed to help out. First, the marines created Detachment One (DET1), an 86 man force of commandoes who worked with the SEALs. DET1 became operational in 2003. The marines already lose a few dozen high quality troops each year to U.S. Army Special Forces, Navy SEALs and air force special operations units. So it was felt that DET1 would reduce this somewhat.
Now SOCOM wants several battalions of marines made available to SOCOM, and the marines are resisting. The marines have noted that once a service lets units go to SOCOM, they never get them back. While SOCOM picks up a lot of the costs of the units they take control of, the service the troops came from still pays lots of the costs. The marines are pretty tenacious in these inter-service battles, and may yet win this one. The marines are willing to provide battalions to SOCOM, as needed, but with the understanding that these units go back to marine control once the mission is completed. Meanwhile, DET1 is still technically being evaluated, as the Department of Defense and the marines have yet to agree on the exact details of how these marine commandoes would work for SOCOM and the marines. This sort of prolonged negotiations are one reason SOCOM considers the marines hard to work with. The marines take that as a compliment.
The U.S. Marine Corps is playing hard to get during efforts to arrange marine participation in special operations work with SOCOM (Special Operations Command). Under pressure from the Department of Defense, the marines have put together a force of training teams for working with foreign armed forces. This relieves the U.S. Army Special Forces of this task. The marines have put together 24 teams, with 13 marines in each one.