The New England Federation funded and performed much of the early space exploration of our own Solar System, and then the colonization of the stars that followed our development of hyperdrives. Near limitless fusion energy reserves and advanced fabricators allowed them to build anything Earth’s space forces needed, and they harvested the Solar System’s wealth to do exactly that. Their large population was easily able to operate an industrial system that used minimal robotic or AI support, and could also send people to colonize other worlds. And they were happy to give opportunities to those immigrants who came through Ellis Island every day. Most of those opportunities were in the New New York trinary star system, or the many Alliance colonies the Federation supported, but they kept enough immigrants on Earth to maintain a healthy population curve there as well.