[motion]

Were there later ORD-CDG flights that you could have taken on the same day? If so, the smart move would have been to get to ORD and try to board another flight. You could have also insisted to be rebooked on another airline, such as Delta, to CDG. Now, you run the risk of things going wrong with your first flight again. If you would have made it at least to ORD, that first segment would have been taken care of and no need to worry. The airline should give you meal and hotel vouchers in ORD. Are you United elite? A mechanical is the airline's fault, so its on them to make things right. If you don't have status, they take the easy way out, assuming you don't know how to push back. Now that its too late, write a complaint letter to United and they should give you a minimum of 25,000 United miles into your account.