Because empire is what the british or europeans do. We were born out of freeing ourselves from an evil empire. So since birth, empire had negative connotations.

Because empire is what the british or europeans do. We were born out of freeing ourselves from an evil empire. So since birth, empire had negative connotations. To say we are an empire means we are just as evil as the british empire or the french empire or the spanish empire. But we are the beacon of freedom, liberty and democracy. So we can't be an empire... Every nation lies to itself.