While nuclear energy promises virtually endless supplies of energy, while producing a fraction of the greenhouse gases compared to coal or oil, it cannot be considered a sustainable energy source until we discover a reasonable way to deal with toxic, nuclear waste. In a growing world, energy demands will continue to increase while fossil fuels dwindle to nothing. If we turn to nuclear energy as our primary energy source, we will have way more nuclear waste than we know what to do with. Inevitably, this waste will have to be stored somewhere, until it is no longer harmfully radioactive (a process that can take generations). Assuming that we are unable to develop technology within the next 50-100 years that can deactivate the radioactive properties of the waste in an efficient manner, we are left with the decision of who gets to bear the burden of toxic waste. However, America has clearly expressed a strong sentiment of NIMBYism (Not In My Back Yard). In this scenario, a Cost-Benefit Analysis could work ONLY if all of the true environmental and health costs are internalized. However, if these costs are internalized, nuclear power would likely be too expensive to be feasible. In the end, until we develop better disposal technologies, nuclear energy is not a sustainable, ethical, or economical answer to our energy demands.