I thought this show was excellent, right up until the point that Brody went home after being turned by the CIA. After that, there were a few exciting scenes but they basically sold out all of the characters to get to those scenes. To the point, where I lost interest.
There were things that bothered other people that didn't bother me at all. For instance, Brody was texting to Abu Nazir from the control room where they were watching a kill team get the terrorist in their sights. Or Brody was on the phone with Nazir from the Vice President's office. Ridiculous, sure, but its an action TV melodrama, so fine. Plus, the basic character of the VP was that he was a phony and a blowhard, so it seems kind of fitting that, in actuality, the security around him was really dysfunctional.
But all of the main players began acting so ridiculously stupid (and counter to character), that it was no longer fun. For example, a deputy director at the CIA was running a US Congressman as a double agent to trap the leading terrorist threat to the US w/o either monitoring him 24/7 or even bothering to inform anyone at a higher level. Implausible, fine, but why on Earth would they do such a stupid thing. No reason. But worse, the deputy director (David Estes) had previously been established as an unctuous careerist who would do anything to help his superiors. But all of a sudden he was doing the opposite for no reason at all.
Then, this character Quinn, who after being established as a "soldier", brought in to be a no questions button man to execute Brody, turns 180 degrees and not only refuses to kill a known terrorist but decides on a whim to become his guardian angel, threatening to kill a high ranking CIA official if any harm might befall his special loved one. The reason was that he decided that Capt. Winters was a straight shooter who had kept his word. Well, pretty much. Except for all those times he went off the grid. Plus, you know, that time he was found alone in the vice-president's office standing over the vice-presidents dead body, which was a bit of a coincidence especially since he had confessed to being on a mission to kill the vice-president. But still, except for that he seemed cooperative, so it totally makes sense that a ruthless killer would devote his entire life to protecting him.
Then, the lead character, who has been established as a character who has obsessed to the point of madness over her failure to stop the 9-11 attacks or save her translator from execution in Iraq, witnesses the murder of 200 Americans, many of who she must have known and worked with over the course of a decade, and decides that the most probably culprit is completely innocent by "seeing into his soul." So certain is she of his innocence that she decides that she must help him flee the scene and the country, without even bothering to check if she might help any of the dozens, hundreds, or thousands of people who must have been injured in the attack. Of course, immediately upon returning from this unexplained disappearance she is herself offered a job as a top level executive.
Not only is that behavior ridiculous and counter to character, but its positively evil. I'm certain that if I watched this show again, I would be rooting for the putative antagonists to catch Carrie and Brody and kill them and be disappointed.
(Plus it was obvious that the actors were so whipsawed by these ridiculous twists, that the acting was terrible)