The M-4 5.56mm "carbine" (an M-16 with a shorter barrel and lighter weight) is attracting a lot of attention because it is the weapon of choice for commandos, and the marines turned it down as their new standard rifle (opting instead for an improved M-16). What most people don't realize is that the M-4 began as a weapons research project by the Abu Dhabi military in the 1980s. A U.S. Marine officer noted the new weapon and brought some back for the marines to evaluate. Congressional politics killed that initiative. While there are many variants of the M-16 being built around the world, the Abu Dhabi version caught the attention of commando forces as well and the U.S. Special Operations Command (SOCOM) picked it up in 1994. SOCOM liked the lighter weight and, in particular, the collapsible stock. With the stock fully collapsed, the weapon was only 29 inches long. For commandos, this compact size can be critical. The M-4 was also equipped with a rail on the top, that made it easier to slip on special sights. The barrel was also easily equipped with a sound suppressor (not silencer.) The only disadvantage of the M-4, compared to the full size M-16, is that accuracy and hitting power of bullets falls off after 200 meters. But since commandos depend on special weapons for long range fire (like the 12.7mm sniper rifle, or the standard squad machine-gun), the M-4 is perfect for them.