The first offensive that the 3rd Division saw was the joint British–American invasion of French North Africa that started on the 8th of November 1942. The Allies organized three amphibious task forces to seize the key ports and airports of Morocco and Algeria simultaneously, targeting Casablanca, Oran and Algiers.
The Western Task Force was aimed at Casablanca and was comprised American units, with Major General George Patton in command. This Western Task Force consisted of the U.S. 2nd Armored Division and the U.S. 3rd and 9th Infantry Division and landed before daybreak at three points in Morocco: Safi (Operation Blackstone), Fedala (Operation Brushwood the largest landing with 19,000 men), and Mehdiya-Port Lyautey (Operation Goalpost).
For more detailed information: http://en.wikipedia.org/wiki/Operation_Torch