The cost of Space-based solar power (SBSP) is enormous and a major cost based rationale is needed for such a project. What if SBSP could be used for defense, desalination and energy independence? If SBSP could solve several strategic problems of the US at the same time then this technology might be cost effective.
I have already explored the possibility of an Airship Powered from Space. SBSP allows for an airship to be an airborne aircraft carrier that can project military power in a way that is not currently available. An airborne aircraft carrier may be the perfect tool for combating threats like ISIL abroad. I actually think this is the least important use of SBSP technology since the US already possesses huge military capacity.
NASA has already explored the use of space-based solar for desalination. The US is already losing millions of dollars in lost agriculture dollars, especially in California, due to land that does not have enough rainfall due to global warming. Global warming will only exacerbate this problem. Agriculture accounts for more or less 1% of total GDP or 170 billion plus. As global warming decimates agriculture around the world our share of the agricultural market could increase dramatically since we took prudent steps to guarantee our water security early on!
The most obvious use of SBSP is the possibility of endless clean energy. The National Space Society has already explored this issue in its article Space Solar Power Limitless clean energy from space. One could argue that the US has been involved in costly wars with little return in Afghanistan and Iraq because of a lack of energy independence. Energy from space means the US has more strategic freedom. The US also spends billions of dollars on oil from outside the US that would be better spent on building our own SBSP energy infrastructure. According to the EIA the Organization of the Petroleum Exporting Countries (OPEC) countries accounted for 56% of U.S. net imports. This is a massive fiscal bleed that we can solve with SBSP.
The availability of cheap energy may also cause a resurgence of manufacturing in the US. The US can increasingly use robotic technologies that are energy intensive to offset cheap labor abroad. The development of SBSP technology means robots in space building the satellite, military robots using the airborne aircraft carrier as a base, and robots in manufacturing that use cheap energy. Taking the lead in SBSP technology means taking the lead in robotics and taking back the future that now appears lost!
The US is facing major problems including military challenges of a terrorist nature, the destruction of agriculture due to global warming and dependence on foreign oil that forces us into military situation that are a lose/lose. The US has traditionally used technology to be at the forefront of all nations. From the Manhattan Project to sending a man to the Moon, the US has stayed ahead through bold technology projects that are only possible at the national level. The rest of the world is catching up with the US technologically and the time has come for the US to once again focus on a bold project that will assure our economic and military supremacy as well as safeguard our security! The US is now in a dark place but I see a future in which that US has global supremacy for the next hundred years or more that surpasses any global role we had in the past!