No, the shipping cannot be shown on the cart page. The shipping address is not known until the customer fills in the checkout form. USPS cannot calculate the shipping without knowing where the package is going. The selection needs to be on the checkout page.
"Also, reinstall the USPS realtime lookup... what I would need to do is open the confirm page and in the server behaviors panel select the plus button and select eCart -> Shipping -> add the US Postal Service rate lookup?"
Yes, that is correct