Asking for trouble(s)

After Avi Becker arguing in Ha'aretz that anti-Semitism is good for the Jews, we now have Jonathan Sarna arguing in The Jerusalem Post that assimilation and alienation from the Jewish community are not necessarily bad for the Jews either.
His reasoning is two-fold: fear of assimilation drives the Jewish community to revitalization; and that "The young, the alienated, and those on the periphery of Jewish life, precisely because they are not wedded to the community's central assumptions, are the most likely to come up with innovative approaches and creative ideas," that ultimately help preserve the religion.
While this may be true in a perverse and paradoxical way, Sarna never really addresses the point that it's a much smaller and tighter community which remains to be revitalized.