Adm. Michael Mullen noted that 17,000 additional combat troops and 4,000 military trainers from the United States will soon be on the ground in the war-torn nation, and said that ultimately they will have "the right impact."
Interviewed Tuesday on ABC's "Good Morning America," Mullen cautioned, however, that "the violence level in Afghanistan is going to go up."
But he said security for the Afghan people is what's missing right now, particularly in the southern part of the country.
Mullen, who just returned from a tour of the Asian nation, said he hopes the training of Afghans to protect themselves can be stepped up significantly in the next few months.
Roadside Bomb Kills Canadian Soldier, Wounds 4 Others
A young soldier just two weeks into her first tour of duty in Afghanistan has become the latest Canadian casualty of the mission.
Trooper Karine Blais, 21, died and four other soldiers were wounded late Monday afternoon when their armoured personnel carrier rolled over a roadside bomb in the Shah Wali Khot district, north of Kandahar.
The young woman was serving with the 2nd Battalion of the Royal 22nd Regiment based at Valcartier, near Quebec City.
A total of 117 Canadian soldiers, including two women, have died as part of the Afghan mission since it began in 2002.
The soldiers wounded in Monday's blast were airlifted by helicopter to a military hospital at Kandahar Airfield despite a fierce sand storm that hit the area. An earlier report that the storm prevented choppers from reaching the scene of the blast was incorrect.
Two of the soldiers were being treated by medical personnel and two were released. The conditions of the two still being treated were not known.
"She was an energetic soldier who gave 100 percent to every challenge she faced using a unique sense of humor, based on her honesty," Vance said. "Frank and direct, she demonstrated the qualities of a future leader who was respected by all members of her squadron."
He said Blais is survived by her mother Josee, grandmother Laurette and brother Billy. Her hometown was not released.
"This young woman's life did not go to waste; she believed in her role in Afghanistan and her dedication to the overall mission is beyond commendable," Vance said.
Blais is the second female soldier from Canada to be killed as part of the Afghan mission.