"The endangered cause" has a layered meaning -- while Don Jose means
Ribierism, it could also, at this critical moment in Decoud's struggle between
skepticism and passion, mean any cause, i.e., "now is the time for
intellect and conscience to accept the validity of passion." In the next
paragraph Decoud proceeds to succumb to the lure of political committment, of
love, in short, of the dream-ideal as embodied and symbolized for him by Antonia.