Continuity mistake: When Nathan stands and greets Agent Folger for the first time he is seen sitting back down on the TV monitor but as the camera angle changes to back inside the room, he is seen sitting down again.
Factual error: The part of the film set in the CIA Headquarters is suppose to take place in 1991. However, Robert Redford's character seems to have both a cell phone and a two-way pager that are quite advanced for the early 1990s. Not to mention the fact that cell phones aren't allowed in places like the CIA headquarters, because they aren't secure and they might allow people to eavesdrop on classified conversations.
Factual error: One of the scenes in the movie shows a lovely green bridge in "West Germany". Too bad this bridge actually is the Szabadság Bridge in Budapest, Hungary.
Continuity mistake: In the part where Brad Pitt arrives at the camp to get the doctor, there's a man with a mutilated arm there, but right after that in the bombing scene the same man is there being retrieved from the building.
Continuity mistake: When Nathan shows the doctor the picture of his parents murder scene, the doctor puts his hand over his mouth. The camera angle changes and the doctor's hand is no longer on his mouth.
Continuity mistake: In the scene where Muir shows Bishop the pictures that prove Hadley´s connections with the Hezbollah, he reaches into his pocket and he takes out one picture only. Yet when Bischop looks at it on the table there are three nicely aligned pictures.
Continuity mistake: When Nathan and Tom are on the rooftop talking, Nathan gets up to leave and Tom is facing to his left. Camera angle changes to a wide view and he's looking at Nathan but when the camera angle changes to a closer view he is once again looking to his left. Happens about 3 times during the entire scene.
Audio problem: When Harry Duncan calls Muer at his house in the opening of the movie you can see that he is talking on a cellular phone in an elevator, yet when he hangs up (you hear it from Muer's end of the line) you can hear the sound of a phone receiver being slammed down. Cellular phone calls end with a polite little beep, there is nothing that makes a physical noise like that. (00:09:05)
Factual error: In the opening Redford crosses the Arlington Memorial Bridge into DC while driving to the CIA. The CIA is not in DC; it's in Virginia and you would never cross that bridge to get there.
Continuity mistake: When Bishop goes to get the doctor he pulls up to the campsite and the items hanging from his rear view mirror are swinging all over the place. The camera angle changes to a driver side view of Bishop getting out of the car and nothing is moving anymore.
Factual error: When Brad Pitt and Catherine McCormack are in a cafe in Beirut in the 80s, the song in the background is a song released in the year 2000 by the Lebanese singer Pascale Machaalani.
Factual error: The Chinese ambulance Tom uses to escape prison when presumed dead reads 'ambulance' on the side in English instead of Chinese.
Continuity mistake: In the scene where Redford asks his secretary to hide Pitt's file, justifying his paranoia with a Noah reference, he puts on his jacket and walks toward the door, leaving the collar slightly upturned. The camera goes to her and then back to him, but when it returns, his collar is perfect.
Continuity mistake: As the van filled with explosives is driving towards the hotel, you see a guard grabbing the doctor and pulling him away. The camera angle changes to a wide view and you see the guard pulling the doctor away again.
Factual error: When Bishop sees Nathan at the train station, his hair is too long for a Marine.
Continuity mistake: Towards the end Commander Wiley is given the order to start operation Dinner Out. The on screen titles indicate that he is near Su Cho but at every other point in the movie it is spelt as Su Chou.
Continuity mistake: When Nathan is making a plate of food, he takes a napkin and puts it under the plate. The camera angle changes to a close-up and the napkin is gone. The camera angle changes to a wide angle and the napkin appears again.
Answer: Muir has become frustrated with the CIA as a whole - now carrying out bugging ops on trade talks so the US can sell more "toaster ovens", as opposed to the 'righteous' work he's done all his career. This is compounded when he sees that the CIA are prepared to let a man (Bishop) be killed over it, which also cements his determination to stop it. Although he has underestimated Bishop's feelings and determination to rescue Hadley, that's not really the point. He sees that Bishop is doing something righteous, 'the right thing' so to speak, and sees rescuing Bishop and Hadley as a chance to a) do something worthwhile again before he retires, b) redeem himself for past sins (sacrificing people/Hadley), and c) poetically stick it to the CIA - using their own resources to carry out the rescue mission amidst the trivial 'work' they're doing now. Muir knows that when he retires he'll be broke, but he'll be able to live with himself - he did something that was morally the 'right thing', as opposed to being the cold calculating operator he's been all his career, with that conditioning being another reason he now resents the CIA (he doesn't like what he's become). He's kicked against the bureaucrats who are doing all the wrong work for the wrong reasons. Also, there's a parallel between Bishop's feelings for Hadley and his attempted rescue mission, and Muir's feelings for Bishop (he loves him like a son or a star student). Muir certainly sees Bishop as family, and you don't mess with an Amercan's family. Muir says as much in the film with the analogy about his uncle's plough horse. The student is now teaching the master - about doing things for the right reasons (love and loyalty as opposed to death and toasters).