NORAD

NORAD is the North American Aerospace Defense Command  that was created in 1957 to provide a air defense system for North America.  NORAD was created to protect the U.S. and Canada during the Cold War from any nuclear threats from the Soviet Union.  NORAD is still in operation and its main headquarters is at Peterson Air Force Base near Colorado Springs, Colorado.
The reason for NORAD was to protect North America from nuclear missles and bombs during the cold war. It was proposed by  Joint Canada - U.S. Military Group in 1956 and was accepted by the United States Joint Chiefs of Staff in 1957.NORAD was created during a time when the Soviet Union was creating many dangerous nuclear weapons that the U.S. have never heard of or didn't know about, so just to be safe, the U.S. approved the idea of creating an air defense system that protected the U.S. and Canada from nuclear weapons and air strikes. The Government thought NORAD was a good idea because it gives people a warning before a bomb/missle actually hits the U.S. or Canada.
Although the NORAD never has prevented us from ever being bombed, it still kept the U.S. safe during cold war and many other occasions. The Systems of NORAD creates a warning if a nuclear bomb/missles come into site near North America. The Defense system will also launch nuclear defense missles if any nuclear weapons show up on the radar/sensors. The system will also set off a alarm to warn the public to get to shelter if we were ever being bombed or attacked.
There are three main NORAD regions which are Alaska, Canada, and The Continental United States.
The Alaska Region NORAD is active 24 hours and 7 days a week which is capable to detect and warn of any threat that comes into the airspace. The main headquarters is located at the Elmendorf Air Force Base. The Canadian Region NORAD is responsible to detect any threats in the Canadian Airspace. The two main headquarters in Canada are located at the Canadian Force Base Winnipeg and at the Canadian Force Base in North Bay Ontario.  The United States Region  is responsible to detect any threats inside the Continental U.S. Airspace. its response system headquarters is located at Tyndall Air Force Base in Florida.
NORAD is one of the only positive things that came out of the Cold War and it has kept the U.S. safe from ever being bombed or attacked from the air.
Fun Fact: NORAD is used to track santa each year.

Sources: http://en.wikipedia.org/wiki/North_American_Aerospace_Defense_Command
              http://www.norad.mil/
              http://www.norad.mil/AboutNORAD/CanadianNORADRegion.aspx
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