goodasgold, yes they should lend money to businesses. But too often they are not and are starving businesses of teh funds they need.
Hardly any of teh bankers on their huge salaries and their bonuses are actually responsible for what happened. They are all just cogs in the wheel. They may think tehy are big fish, but tehy aren't and, just like Fred the Shred, their fortunes can change in a flash and they can get laid off just like anyone else.
The real decisions are made right at the top. The system is established right at the top, and all the rich bankers are just employees working for the system. But those right at the top knew the game, they loosened credit, knowing they would eventually pull the plug and rein it back in. They allowed the derivative gambling to continue, knowing tha tthey would eventually pull the plug. As always these things are done for power and money and influence by billionaires (many of whom give lavishly to charity).