Tank Dempsey

 Tank Dempsey was an American Marine of the Marine Raiders. 

Personality
Tank Dempsey: American hero. Give him a loaded weapon,a good woman,and something to shoot at and he’s happy. Cross him and he’ll rip your guts out and use them as a bandolier. Dempsey was selected for this mission after he showed his true grit at the battle for Peleliu. His unit was captured during the early raids before the main invasion, and he spent two weeks in a rat infested bamboo cage submerged in malarial water. Eventually, he gnawed his way through the cage, and then gnawed his way through his captors armed only with a Bobby pin and his Medal of Honor which he keeps secreted in various body cavities. There is no before the war for Dempsey, there is no after. There is only the legend of Tank Dempsey, and how he won the war for the rest of us.

In an article on the CIA database in Black Ops it says Tank, along with Takeo, had their minds wiped by Element 115. It also says Richtofen is observing them.

It should be noted that Tank is slowly regaining his memories judging by quotes from Ascension.

Tank's rank is at least sergeant as he has lead numerous recon missions for the Marines. One of his most notable was his mission to extract Peter from the Asylum, but it ended horribly.

He has a somewhat admiration for Takeo's skills, but the feeling is not mutual. Tank also hates Richtofen.