Like what? Name a single one!
Space exploration has stagnated precisely because it has relied on whether governments can find such an incentive. Everything substantial costs effort and resources to acquire and make, and rockets, being among the most tedious and expensive things in the world to make, are as bound to this as anything.
The cold war is over, and every politically convenient reason that might have helped push scientific progress into deep space has vanished--or do you think the general public actually cares about that when their national pride is no longer being measured against another superpower? A far better source of money--and someone has to pay for it, somehow--is not the inefficient, bureaucracy-clogged, slow, generally space- and science-disinterested funding apparatus of the US (or any) federal government, but people and companies with money who will hand it over to whichever people require the least of it to get a payload into space, whether commercial or scientific.
Musk knows the same thing Wal-Mart does: If you charge less by the right amount, you can make more money by drawing business away from relatively expensive competitors. When your competitors are comprised almost entirely of long-established aerospace contractors that have not had to worry about running efficiently for decades, it doesn't take much of a difference. He's not losing money by doing this, in hopes of making it back later. He's set to make the stuff hand over fist--by charging less. The financial environment of space exploration and aerospace research as we know it is unnatural, and arose only because, for a time, the technology was so expensive that it took nothing less than the budget of a superpower (back when it still had a red, hammer-and-sickle-adorned fire under its ass) to so much as get the field started. That's not true anymore.
You want astronauts exploring asteroids? Find a way for somebody to make a buck in the process, and it'll happen--and it'll be easier than convincing some world government to fund such a program.