From my perspective infrastructure is politically driven in the US. Projects are debated for decades, over this time changes are made to placate some groups and buy the support from other groups, and create jobs for some politician, until it baloons into something that is many billions of dollars. Then it is built as a one off mega project. At this point it should be killed but this is seen as the only way to get stuff done.

Things like CAHSR instead of agreeing on a goal and deciding we should have a CA-wide rail system, so then establish a division of Caltrans which we fund to incrementally build/acquire/run a network through ROW acquisition, running DMUs on the routes in the mean time, making it compatible with existing systems, etc. instead becomes one giant $60b acquisition that is master planned for a multi decade time frame to be built almost entirely as a stand alone system the benefits of which can't really be enjoyed until decades in the future.