Most environmental groups take positions on issues such as conservation of the existing environment, clean air and water, and protecting biodiversity. In each case, they are reacting to the devastation of the Earth's environment caused by our technological civilization. The focus is on slowing and eventually stopping the damage we inflict on the Earth. This approach tends to focus on the past up until the next fifty years or so. Space advocacy groups work on opening up the opportunities of space and convincing our government to open up the Final Frontier to organizations and businesses outside of the public sector.
Some space groups recognize the fact that the Earth is basically a closed system.
There is an eventual limit to how many humans can live here. The basic message of the LUF is that the future is something that we, as individuals can create together, rather than allowing it to simply happen to us. Many people fear the future. In addition we are trying to create a comprehensive vision for the future. We are looking ahead to as far as 1000 years to see what a true space faring civilization would look like and we are trying to make that vision real.