USPS is trying, and failing, to compete with the big boys in the shipping and mailing business. FedEx and UPS are the Coke and Pepsi of the shipping business, while USPS is the RC Cola. In an effort to gain market share, USPS offers many of the same services as the two market leaders. These include Overnight, International and Packages and Boxes.
The solution is to do the opposite of what they are doing now. Instead of trying to compete with the big boys and offering the same things they do, USPS needs to narrow its focus and offer something they can't. But what can the USPS offer that a corporation with lots of money can't?
That uniquely shaped box on a pole with the little red flag outside every home in America. FedEx can't compete with the USPS delivery to the mailbox. USPS basically owns them. That's the focus. That's the niche for success.
And if it can't fit inside a mailbox, DON'T SHIP IT. Period. No exceptions
Companies succeed when they find a niche that they can be the leader in and stay focused on it. FedEx is overnight. UPS is ground. USPS should be the mail.
This is what Southwest did in the Airline business. Instead of trying to compete with Delta and American Airlines, and offer everything they did and fly everywhere they did, Southwest found a niche and stuck to it. They focus on interstate, point to point, low cost flights. They don't offer first class or inflight meals. They don't fly internationally and they don't fly to tourist destination. And they only have one type of airplane, which cuts down on maintenance and training costs. And they are profitable.
If it doesn't fit in a mailbox....
Don't ship it. This means letting go of anything that is overnight, international or in a box. Leave those to FedEx and UPS, they are the leaders in those anyway.
Dropping these other services will greatly reduce cost and will simplify the whole company. It will greatly reduce the extras needed to run the company. Like, special planes to fly a package across the country overnight, or a plane to fly a package to another county.
Focus on the mail. Stuff you can put a stamp on. Leave the rest to the other guys, who are already beating the USPS at it anyway.
Beat them at the Mailbox.