That's more than a decade less than what Chelsea Manning or John Kiriakou was sentenced to. It's absurd that the punishment is much harsher for unspecified theoretical harm caused by whistleblowing than the very real harm caused by literal murder attempts.
Crimes against the state or that that thumb their nose at the authority of the state always carry disproportionate punishments because the state is who's writing the rules, running the systems, creating the sentencing guidelines, etc.