We've been working on CATS for decades
Rockets are orders of magnitude cheaper than the Shuttle. We will save boatloads of money using the rockets we currently have to launch the new CEV. Some of that money can then be used to create economic incentives in the private sector with prizes. If we do that CATS will emerge sometime within the next decade or so. If we try to do it the same as we have for the last 40+ years, all we'll have is 40 more years of DOGS (Dumb Old Government Subsidies).