It's more than the idiotically dense plot twists and implicit transporter beams zapping principles from location to location.
24 sucks for me because it's a season-long ticking bomb used to justify torture and the police state.
The very premise is a set-up, after the first season, in which the idea of an imminent disaster might have been at least relatively described as novel. Now into season 3 or 4 (does it matter?), the well-established premise broadcasts a norm of what to expect from our government. Remember back in the 90's when some people were suggesting that
The X-Files was a means for making people familiar with the idea of aliens living among us? Well,
24 fulfills the same function for the police state.
As evidence for this assertion I point to this past week's episode, in which the first thing the terrorist mastermind does upon learning that one of his henchmen has been captured is to phone 'Amnesty Global', so that they'll send one of their lawyers down to get him off on a technicality. I should mention that even though this guy just killed a man in the presence of 20 law enforcement officers, the tactic works - not withstanding the fact that the nation is in the midst of a nuclear emergency directly involving the suspect.
So here's a fascinating thing: this idiotic plot development is intimately linked with the police state mentality that sees human rights organizations as slimy henchmen for terrorist thugs. Likewise in the same episode, the endlessly resourceful terrorist mastermind nabs a nuclear warhead as it's being moved to a decomission facility, in accordance with some arms reduction treaty. Even when it's not aggressively corrupt, on 24 liberalism (in the form of diplomatic accord) is nonetheless a dangerous vulnerability we can't afford.
The plot of this season's 24 is quite like Bush Co's endlessly shifting rationales for going to war in Iraq. Even though they've only got a day's worth of time to fill up, the crisis keeps shifting from one doomsday scenario to the next, leaving the agents of CTU perpetually tasked with thwarting the ticking timebomb. And this archetypal day presents a sort of microcosm of the perpetual war on terror, wherein torture is duty and individual rights are a crime against the common good.