Are you talking about private sector space exploration/research or just in general? Because I fail to see how the aforementioned private sector industry would cease to exist without NASA.
Sorry that I was unclear. I was, of course, referring to the private sector when it comes to space. I think NASA and other government agencies are vital to ensuring that private space exploration sector exists. It's not that I believe NASA is necessarily vital to ensuring that space exploration and research happens. However, I do not believe the free market alone is anywhere near enough to sustain such an industry. As I said above, NASA's mission should be changed and public-private partnerships should be heavily pursued. We need both government and the private sector if we're going to take humanity beyond Earth (let alone discover life on other worlds).