It creates a cascading effect. There's an insane debt bubble and a lot of that debt will lose rating, so many investors will drop it creating a feedback loop. Dumb money have to drop it because of their mandate and/or rules, even if this is bad for their other assets (i.e. more debt they hold).

This would be the dumbest idea right now. I hope government agencies worldwide can resist the attack from media.

[Don't get me wrong, fuck banks, evil hedge funds, and speculative landlords, but they are barely going to be hit by something like this.]