Hi,
You might need to change the dimensions and weight units for the USA country and use LB/IN instead of KG/CM.
Also, in the rest of the settings you need to select shipping services. If you didn't select national shipping services and only international shipping services, it would also explain why you don't get shipping services.
One interesting thing you can do is to deactivate the USPS shipping method to only have the UPS shipping method. That way, when no shipping methods are found, the UPS shipping plugin will display an error message explaining why it can't retrieve the shipping fees. That should help you understand what's wrong.