Why do assume it was the terrorists who fed the government the misinformation? Personally I suspect the makers of duct tape and plastic wrap did it as a way of upping their sales.
Seriously though, I don’t think there’s enough info in the article to go on. First off, could a dirty bomb actually be encased in a shoe? And I mean an effective one that would scatter radioactive material for blocks. Also are we sure ABC got it right? Maybe what was said was that the material for the bomb was smuggled in that way, not the whole bomb itself.
I think that the govt. should’ve given the informant a lie detector test earlier and maybe saved some people some anguish, but OTOH, they didn’t raise the threat level to aqua/purple plaid, or whatever the highest level is. If the govt. had raised it to the highest level I would be a bit more perturbed. Let’s remember that they only said there was an increased chance from previous weeks that a terrorist attack was likely, not a definite chance.
And let’s also remember that the article linked to in the OP states that they have other info that a terrorist attack is still likely, so there may still be a legitimate reason for the raising of the threat level, and people reading too much into the shoe thing and accusing the govt. of overreacting are forgetting that there’s still other info about potential terrorist attacks that we the public don’t have.
On a final note, I went into D.C. last night to see Rent at the Warner Theatre, which is only blocks from the White House, so neener-neener to the terrorists and the makers of duct tape. No point living in fear of something you can’t control.