Vakoch admits that the typical SETI approach has been to suppose that long-lived extraterrestrialcivilizations would also be far-ranging technical wizards.
But because earth is home to the only technological civilization thus known, we are severely hamstrung when making assumptions about the longevity of potential extraterrestrialcivilizations.
Thus, in an age when we have come close to destroying ourselves several times over, is it reasonable to expect that extraterrestrialcivilizations would persist over lifetimes of hundreds of thousands if not millions of years?