Operation Torch was the first joint military operation planned by Great Britain and the USA.
In November 1942 ~ 850 U.S., British, and Allied warships (the largest invasion force in the war up to that date), commanded by General Dwight Eisenhower, landed at Casablanca, Oran, and Algiers in an attempt to wrest North Africa from the Vichy French.
After several days of fighting, the Vichy French forces surrendered and the Allies advanced eastward against Italian and German forces in Libya and Tunisia.
With victory in North Africa, the Allies hoped to gain control of the Mediterranean Sea, then invade Sicily, mainland Italy and the “soft underbelly” of Europe.
read more: http://en.wikipedia.org/wiki/Operation_Torch