There are three levels of difficulty in innovation: New Engineering, New Science, and New Fundamentals. What the Wright Brothers did was the easiest of the thr

There are three levels of difficulty in innovation: New Engineering, New Science, and New Fundamentals. What the Wright Brothers did was the easiest of the three: New engineering. It didn't contradict anything then known in accepted science. Fusion energy is being studied now, and it's substantially more difficult than what the Wright brothers did because it requires New Science. But it doesn't violate any of the accepted fundamentals of the universe, so it will probably happen eventually. Now we come to the most difficult of the three: New Fundamentals. Traveling to other galaxies falls in this category. For it to work we would have to discover some brand new principle that makes the universe work, and that principle would need to be so radical that it makes what we now know about the laws of physics wrong. That's not likely to happen. By comparison, the Wright brothers' invention was for all practical purposes inevitable; people had been flying heavier-than-air craft like gliders and kites for hundreds of years. All that was needed was an energy-dense power plant.