On September 9th, a German container ship, seized by pirates off the north coast of Somalia, was retaken by ships from the anti-piracy patrol. The eleven man crew had shut the engines down and got to a safe room as the pirates boarded. Warships showed up shortly and convinced the pirates to leave, or be killed. This was done by sending a platoon of American marines to board the ship and convince the nine pirates that resistance was futile.
The marine force was described as the Maritime Raid Force, a special group of marines trained for just this sort of thing (getting onto a ship controlled by pirates, and quickly overcoming the pirates and rescuing the crew). The concept of having a Maritime Raid Force with a MEU (Marine Expeditionary Unit, a reinforced battalion) arose after the end of the Cold War (1991). MEUs travel on the carrier-like amphibious ships that the U.S. Navy deploys all over the world, usually in conjunction with a carrier task force.
The marines correctly surmised that, with the Cold War done, they would now be dealing with a lot of peacekeeping type operations, and "special operations" in general. This could range from evacuating American civilians from a combat zone, to hostage rescue and various types of raiding or reconnaissance. In repose, the marines developed special training courses for their MEUs, and declared units that passed the test for a course "Special Operations Capable" in a particular skill. That SOC designation lasted less than a year, after that the unit had to be tested and certified again. This made training a lot less repetitive and a lot more exciting. That, plus the fact that most marines, especially the NCOs, are now combat experienced, and it should be no surprise that the marines retook that container ship on September 9th without a shot being fired, and no one injured. Another little reported aspect was how the training of navy personnel (ship and aviation) was also part of the SOC process, and particularly the Maritime Raid Force effort.
Meanwhile, the marines have also joined SOCOM (Special Operations Command), the traditional special operations outfit. Three years ago, the U.S. Marine Corps Special Operations Command (MARSOC) had 2,500 personnel declared "operationally capable." The marines basically lost two of their four Force Recon companies (one of them a reserve unit) in order to build MARSOC. Meanwhile, more troops have been added to division level reconnaissance units, to take up some of that slack, and replace the lost force recon capability. The Special Operations companies (with about 120 personnel each) can provide Force Recon capabilities to marine units they are attached to. The MEU involved in the September 9th operation had a Force Recon platoon attached, and those troops formed the core of the boarding force.
The Marine Special Operations Regiment consists of three Special Operations Battalions providing a combination of services roughly equal to what the U.S. Army Special Forces and Rangers do, as well as some of the functions of the Force Recon units. Each Special Operations Battalion consists of four Special Operations Companies, and each of those consists of four Special Operations Teams. These have fourteen men each, and are commanded by a captain (O-3). Battalions and companies also have some command and support personnel.
The marines finally got around to working with SOCOM in late 2005, when it was agreed that they would create a marine special operations command. The Marine Corps had long resisted such a step, largely because of its belief that marines are inherently superior warriors, capable of highly specialized missions. This attitude began to change during the fighting in Afghanistan, when marines were assigned to support SOCOM troops there.
As a result of that experience, marines were attached to SOCOM for liaison and observation purposes. In 2004, the marines organized a company sized unit of commandos, "Detachment One", using volunteers from their Force Recon troops, the closest thing the marines had to commandos. Detachment One was sent to Iraq, where it's performance convinced SOCOM that marines could operate at the SOCOM level.
The U.S. Marine Corps special operations effort was inspired, in part, by the experience of the British Royal Marines. This force adopted commando tactics and organization during World War II (they were part of the original "commando" force), and kept the commando organization and training after World War II. The British Army disbanded their commando force, and the Royal Marines reduced theirs, but the Royal Marine Commandos still exist, and have compiled an impressive record since World War II.