The wealthy people that control politicians the law, the economy and everything else thought it was. It is good for them to keep the status quo and keep their place high on the rungs of society. If the markets broke down we would have a depression and perhaps a revolution.
The purchase of bad assets was an effective move for the US treasury during the chaotic economic status of the United States during that time. The assets whether bad or good provided the economy with the push that was needed to bring the country out of a slow recovering economy.