http://www.nytimes.com/2008/04/20/magazine/20wwln-safire-t.html?_r=2&ref=magazine&oref=slogin&oref=slogin
"The primary meaning is evident from the context: to be in the tank
is to be “lovingly enthralled; foolishly enraptured; passionately
bedazzled.” A more sinister meaning, however, hovers in the shadows:
“self-interestedly involved; surreptitiously supportive” and in extreme
cases “corruptly influenced".”
"from a 1930 Los Angeles Times: “The Illinois Boxing Commission today probed the alleged confession
of James Gary . . . in which Gary was said to have stated that he did a
nose dive . . . and reached the conclusion that Gary had been knocked
cold and that no effort had been made to put Gary in the tank.”
"A
tank was the 19th-century term for what we now call a swimming pool;
the metaphor evoked a picture of diving to the ring’s canvas-covered
floor — as if into a pool — to feign loss of consciousness. “By
extension,” Dickson reports, “when a fighter or anything else
(including a stock) takes a nose dive he or she has tanked.”
"While we’re in this examination of the many meanings of tank,
we come across its use as an attributive noun in fashion’s tank top.
That sleeveless T-shirt is so named because it was originally worn by men and
women long ago for swimming in the pool, or tank"
Safire nails the meaning in that the MSM is "lovingly enthralled", "foolishly enraptured, and "passionately bedazzled" with Obama. It's classic liberalism: symbolism over substance. Where are the insightful, hard hitting, difficult questions from our press? Instead we get

Mark