Well I am sure Goldman Sachs would use the "fired for cause" excuse to get away with it. Even with union, you can be fired still with cause and all Goldman Sachs need to do is demonstrate that those traders lost money for the company and that's causing damage to the company and that's cause. When you are a trader, losing money is unavoidable. And even if we traders all get unionized, Goldman Sachs would just fire all of them and replace them with machines.