Continuity mistake: In Cale's interview, just before agent Todd starts making a noise, Maggie is holding a fact sheet about Cale. The way she holds it changes between shots. (00:16:40)
Continuity mistake: When Cale asks his ex-wife what he has done, he has the envelope he is holding in one hand in one shot and both hands in the next. (00:10:05)
Revealing mistake: When we see Cadillac One cutting over some grass, marks from previous takes are visible. (01:12:50)
Continuity mistake: When John and Emily are in the car at the start, the way John holds the envelope changes between shots. Note the flap. (00:11:20)
Answer: Knowing is not believing. They might know, but they wouldn't necessarily trust the media. After all it could have been a grand conspiracy to cover up the actual truth from the people.
Alan Keddie
I highly doubt world war 3 would start before these countries did their homework though. It wouldn't take long for them to suss out it was actually terrorists who detonated the bombs and not America.
The_Iceman