Now, to step away to the politics (which was not the purpose of this thread) and more to the subject at hand: The performance of the round in non-military applications.
The wikipedia article on 5.56 NATO is pretty good. See
http://en.wikipedia.org/wiki/5.56×45mm_NATO
It cites, among other sources, "Do We Need a New Service Rifle Cartridge?", Small Arms Defense Journal, 6 January 2012.
Per this source:
If 5.56 mm bullets fail to upset (yaw, fragment, or deform) within tissue, the results are relatively insignificant wounds. This is true for all 5.56×45mm bullets, including both military FMJ and OTM (open tip match) and civilian JHP/JSP designs used in law enforcement. As expected, with decreased wounding effects, rapid incapacitation is unlikely: enemy soldiers may continue to pose a threat to friendly forces and violent suspects can remain a danger to law enforcement personnel and the public.
This failure of 5.56×45mm NATO bullets to yaw and fragment can be caused by reduced impact velocities as when fired from short-barreled weapons or when the range to the target increases. Failure to yaw and fragment can also occur when the bullets pass through only minimal tissue, such as a limb or the chest of a thin, small statured individual, as the bullet may exit the body before it has a chance to yaw and fragment. Two other yaw issues: Angle-of-Attack (AOA) variations between different projectiles, even within the same lot of ammo, as well as Fleet Yaw variations between different rifles, were elucidated in 2006 by the Joint Service Wound Ballistic Integrated Product Team (JSWB-IPT), which included experts from the military law enforcement user community, trauma surgeons, aero ballisticians, weapon and munitions engineers, and other scientific specialists. These yaw issues were most noticeable at close ranges and were more prevalent with certain calibers and bullet styles—the most susceptible being 5.56x45mm NATO FMJ ammunition like SS109/M855 and M193.
There are also sketches of wound channels. It jogged my memory back to the time of the Vietnam war when the cartridge was adopted. I remember reading press reports about the wound channels created.
I am still wary of using it on anything bigger than a coyote. However, I did pick up 250 rounds to try out.
We shall see.