Chinese scientists plan a solar system-wide space resource system by 2100, with resupply/water depots out to Jupiter and have identified 122 near Earth asteroids for mining.
What if you could mine all the resources you need for space exploration from space itself? China reveals plans to set up an extensive space resource system.
In fairness to China, they have a pretty good record of setting out space plans and sticking to them. Assuming re-useable rockets become widespread, getting to space should be much cheaper. Using the solar system's legrange points (as they propose here) has long been recognized as key to being able to regularly travel around the solar system.