The mandate of the biblical regime was to devise a better way to occupy a sovereign homeland; the mandate of the rabbinic regime was to introduce a better way to live in exile.
The destruction of the Temples demonstrated the failure of the biblical regime; first the spiritual and then the physical collapse of European Jewry demonstrated the failure of the rabbinic regime.
The argument for the establishment of the State of Israel is not that the Jewish people had come to learn how properly to live in exile; it is that the Jewish people finally had failed in their exilic experiment. There was nowhere left to go for the Jewish people but back to the homeland, back to the biblical regime, back to the embracing of the responsibilities of sovereignty and dignity and national autonomy.
It was not only the rabbinic regime that failed in diaspora, the secular Jews failed just as completely. By the middle of the 20th century, exile had been shown to be a failed strategy for national existence for any sort of Jew, be they traditionalist or modernist.