It's chosen because airport and highway expansions also cost many billions, and at least on paper HSR often pencils out. California studies showed that alternat

It's chosen because airport and highway expansions also cost many billions, and at least on paper HSR often pencils out. California studies showed that alternatives centered on airport and/or highway expansions without HSR would have also cost tens of billions, and altogether ultimately more than a master plan including HSR. AFAIU the same analysis is true for the NE. CAHSR costs ballooned, but so do highway and airport expansions. The U.S. and many other countries have cost management problems with all large infrastructure projects.