When the show debuted my wife became an immediate huge fan. I was less than thrilled. First off, I couldn't stand the constant bi-polar-type crying jags the female star, Danes, frequently engaged in for whatever reason.
Then I detected subtle hints that the writers were trying to steer the show into a moral equivalence thing despite the few patriotic utterances by a some of the characters.
Then Danes's character has a fling with Damian Lewis. Yeah, like all counter-intelligence agents do. Sure.
In short, I just didn't like the show. Way too much emoting and "we're just as bad as they are" kind of moral equivocating even in the early episodes.