That path is best approached with tourism and media experience
NASA won't lead us to a sustainable space presence with their planned manned activities. Private enterprise is much more promising in that regard. Being defined by a profit motive and willing to sell and market every aspect of the experience, they're business models will be a sustainable bootstrapping process.
NASA could support and complement this process by doing experimental work to understand health effects and the automated probe work to locate resources and figure out ways of accessing them reasonably.