I did read all of it. I just did again, and I'm still not getting what you mean. Is 'the U.S' referring to the Enclave, or what they called their community? Regardless, you'd still be off by about 200 years.

Note the bold:
[quote]Upon discovering the Enclave, the soldiers happily obeyed their directives until [b]2080[/b], when under the constitution a presidential election was to be held.[/quote]

The current year is 2282. 

Maybe I'm missing something cleverly hidden, but as I understand it, he'd have to be over 200 years old to have attended an academy, survived the nuclear war, and met the Enclave afterwards.