A minimum wage of 10-12 dollars is a little high. There have been two times in my life I've worked for minimum wage. Once when I was a teen, then again in my mid twenties when I went to work for McDonalds.
The experience at McDonalds taught me that you do get paid what you are worth if you will actually work. We had a very "hands-on" owner/operator. I stayed at minimum wage for about two weeks, was promoted to management in about 4 months. That was how our owner worked. If you can to work when you were supposed to, and worked while you were there, he would give you a raise.
Minimum wage jobs tend to have a very high turnover rate. It costs a company money to hire and train folks. We would usually have to hire about 8-10 people at a time because out of those, only 2 would actually come to work. It was alot of paperwork to obtain two good employees. Those that actually stayed and would come to work always got raises every 3 months.
I think the problem is really all the corporations sending all the manufacturing work to China and Mexico. They don't pass the savings along to us, it goes to the CEO's and shareholders. The working-class that used to be the backbone of America are falling by the wayside.
A global minimum wage would make sense, but American corporations would fight that and with all their money and political power they would defeat that idea.