I had the same conclusion initially and called it the horizont of space reachability principle. There is a limit to the travel distance defined by the energy co

I had the same conclusion initially and called it the horizont of space reachability principle. There is a limit to the travel distance defined by the energy consumption. Reducing the energy consumption to the minimum would allow to extend this horizont limit. Pushing this reasonning to its limit I noticed that we have plenty of examples on earth of live forms able to extend this limit to infinity by mean of seeds or spores form. In such form the organism is totally passive and consumes no energy. It has a trigger which induces reactivation of life and development that may be activated by external energy and appropriate condition. So it is possible for a life form, human or extraterrestrial, to build such a civilization seed which contains enough energy reserve and machinery to sustain life activity restoration and live form rebirth. Throw such civilization seed vessel like a bullet toward a distant solar system so that the energy of the target can be used to trigger start of development and we have our space travel capacity. This is not how we'd naturally imagine interstellar travel, but the important point is that this proves that it is possible without relying on exotic or hazardous hypothesis. We should also keep in mind that there is still the possibility to tap into the dark matter as source of energy. While this is still very uncertain, it should be known and well accepted By now that interstellar travel and space colonization is possible. I would like to add to this that if human life is a result of a natural process, there is a very high likelyhood that we are not alone in the univers and that other entities are likely to have started colonization already a long time ago. As we can see from earth civilization history a key factor to perserve its liberty and life autodetermination is the mastering of science and technology, intelligence and defense capacity. While there is still a need to protect ourselves from oher humans, in which we spend and waste a lot of ressource, the clock is ticking, and other civilizations may be developping much faster and efficiently than humans. It is no hard to see what it all implies.