It's a combination of many things as for why it's not working.
Bush and Clinton essentially let Wall Street do whatever the heck they wanted. The Republicans, way more than the "socialists" are to blame though. They had Bush as president, a Republican House, and a Republican Senate. What did they do other than fail the American people?
Then you have Obama who would have been a better president had he done absolutely nothing. He didn't cause the crisis, he contributed to it at an alarming level.
Funny thing is, let me remind you of "Socialist Sanders" views:
Against unregulated Wall Street
Against NAFTA
Against the War in Iraq which was an inexpensive, unnecessary, and dangerous war
Against the bail outs
But it's Bernie Sanders fault...