The problem with space travel, if we can ever approach or even exceed the speed of light, is that it will only be of use for the people on the ship. Let's say we have a craft that can travel to the nearest star Alpha Centauri, 4.3 light years from Earth. They can do the speed of light, so they go there and back, an 8.6 year journey. Problem is, when they get back home tens of thousands of years will have passed on Earth. We can thank Einstein and his Relativity for that bit of bad news.