Having been a fan of previous series; (for their credibility of story and action; as well as the portrayal of Americans as not always being ultra-good):
This series spiraled out of control from early on. The lack of credible actions toward the end of the series is a major problem for the quality of the overall programme.
Some of the scenes, events and outcomes were frankly ludicrous and unbelievable. By the end the star-spangled rhetoric was nauseating. I don't blame the directors or actors; they maintained their quality of performance throughout. I blame the writers. They ruined this. A real shame.
The writers should be ashamed.