If every single one of the plots you noted (including the ones that were actually reverse stings organized by the FBI) was wildly successful, terrorism would kill about as many Americans as accidental gun discharges do. And that's not realistic.
Terrorism is bullshit. Sadly, we can't do the right thing because the country is full of cowardly morons who think that the solution is toppling more governments, killing more people, and hoping that somehow this time will be different.
Terrorism is bullshit. Sadly, we can't do the right thing because the country is full of cowardly morons who think that the solution is toppling more governments, killing more people, and hoping that somehow this time will be different.