I am calling for a unified international effort to explore and utilize the Moon, a partnership that involves commercial enterprise and other nations building upon Apollo. Let me emphasize: A second “race to the Moon” is a dead end. America should chart a course of being the leader of this international activity to develop the Moon. The United States can help other nations do things that they want to do, a fruitful avenue for U.S. foreign policy and diplomacy.

A step in the right direction is creating an International Lunar Development Corporation, customized to draw upon the legacy of lessons learned from such endeavors as the International Geophysical Year (whose purpose was to get scientists all over the world to focus on the physics and atmosphere of the Earth), the International Space Station program, as well as model organizations such as Intelsat and the European Space Agency. Space collaboration should be the new norm, including the tapping of talented Chinese, Indian and other space experts from around the globe.

In my view, U.S. resources are better spent on moving toward establishing a human presence on Mars. I envision a comprehensive plan that would lead to permanent human settlement on Mars in the next 25 years. To get under way, the International Space Station can serve as a test bed for long-duration life support and for technologies that can safely, reliably and routinely transport crews to the distant shores of Mars. I’ve championed the creation of spacecraft to be placed on continuous loops between Mars and Earth, thereby putting in place a pathway to sustainability that forever links the two planets.

Going to Mars means staying on Mars — a mission by which we are building up a confidence level to become a two-planet species. At Mars, we’ve been given a wonderful set of moons — one of which, perhaps Phobos, can act as an offshore world from which crews can robotically preposition hardware and establish radiation shielding on the Martian surface to begin sustaining increasing numbers of people. To succeed at Mars, you cannot stop with a one-shot foray to the surface.

My passion for space exploration is guided by two principles: a continuously expanding human presence in space, and retention of U.S. leadership in space. To move forward, what’s required is what I term as a Unified Space Vision for America that is predicated on exploration, science, development, commerce and security. To reach beyond low Earth orbit requires a suite of missions that are the foundation for such a Unified Space Vision. Putting in place and staying on track with this unified approach must begin now.