They do in fact have their own shortener (https://go.usa.gov/ https://go.usa.gov/)... but after abuse, they changed it to require a login so I'm guessing there

They do in fact have their own shortener (https://go.usa.gov/ https://go.usa.gov/)... but after abuse, they changed it to require a login so I'm guessing there was an issue hardcoding someone's login to let the API generate them?